Fix always re-run testsuite issue

- This issue is report by Nelson.

 - Don't using build-sim as dependency, it will cause the Make always
   rebuild.

Makefile.in

@@ -162,22 +162,21 @@ report-binutils: report-binutils-@default_target@
 report-gdb: report-gdb-@default_target@
 
 .PHONY: build-sim
-build-sim:
 ifeq ($(SIM),qemu)
 SIM_PATH:=$(srcdir)/scripts/wrapper/qemu
 SIM_PREPARE:=PATH="$(SIM_PATH):$(INSTALL_DIR)/bin:$(PATH)" RISC_V_SYSROOT="$(SYSROOT)"
-build-sim: stamps/build-qemu
+SIM_STAMP:= stamps/build-qemu
 else
 ifeq ($(SIM),spike)
 # Using spike simulator.
 SIM_PATH:=$(srcdir)/scripts/wrapper/spike
 SIM_PREPARE:=PATH="$(SIM_PATH):$(INSTALL_DIR)/bin:$(PATH)" PK_PATH="$(INSTALL_DIR)/$(NEWLIB_TUPLE)/bin/"
-build-sim: stamps/build-spike
+SIM_STAMP:= stamps/build-spike
 ifneq (,$(findstring rv32,$(NEWLIB_MULTILIB_NAMES)))
-build-sim: stamps/build-pk32
+SIM_STAMP:= stamps/build-pk32
 endif
 ifneq (,$(findstring rv64,$(NEWLIB_MULTILIB_NAMES)))
-build-sim: stamps/build-pk64
+SIM_STAMP:= stamps/build-pk64
 endif
 else
 ifeq ($(SIM),gdb)
@@ -190,6 +189,8 @@ endif
 endif
 endif
 
+build-sim: $(SIM_STAMP)
+
 stamps/check-write-permission:
 	mkdir -p $(INSTALL_DIR)/.test || \
 		(echo "Sorry, you don't have permission to write to" \
@@ -793,17 +794,17 @@ stamps/build-dejagnu: $(srcdir)/riscv-dejagnu
 	mkdir -p $(dir $@)
 	date > $@
 
-stamps/check-gcc-newlib: stamps/build-gcc-newlib-stage2 build-sim stamps/build-dejagnu
+stamps/check-gcc-newlib: stamps/build-gcc-newlib-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gcc-newlib-stage2 check-gcc "RUNTESTFLAGS=--target_board='$(NEWLIB_TARGET_BOARDS)'"
 	mkdir -p $(dir $@)
 	date > $@
 
-stamps/check-gcc-newlib-nano: stamps/build-gcc-newlib-stage2 build-sim stamps/build-dejagnu
+stamps/check-gcc-newlib-nano: stamps/build-gcc-newlib-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gcc-newlib-stage2 check-gcc "RUNTESTFLAGS=--target_board='$(NEWLIB_NANO_TARGET_BOARDS)'"
 	mkdir -p $(dir $@)
 	date > $@
 
-stamps/check-gcc-linux: stamps/build-gcc-linux-stage2 build-sim stamps/build-dejagnu
+stamps/check-gcc-linux: stamps/build-gcc-linux-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gcc-linux-stage2 check-gcc "RUNTESTFLAGS=--target_board='$(GLIBC_TARGET_BOARDS)'"
 	mkdir -p $(dir $@)
 	date > $@
@@ -814,7 +815,7 @@ check-dhrystone-newlib-nano: $(patsubst %,stamps/check-dhrystone-newlib-nano-%,$
 
 stamps/check-dhrystone-newlib-%: \
 		stamps/build-gcc-newlib-stage2 \
-		build-sim \
+		$(SIM_STAMP) \
 		$(wildcard $(srcdir)/test/benchmarks/dhrystone/*)
 	$(eval $@_ARCH := $(word 4,$(subst -, ,$@)))
 	$(eval $@_ABI := $(word 5,$(subst -, ,$@)))
@@ -823,7 +824,7 @@ stamps/check-dhrystone-newlib-%: \
 
 stamps/check-dhrystone-newlib-nano-%: \
 		stamps/build-gcc-newlib-stage2 \
-		build-sim \
+		$(SIM_STAMP) \
 		$(wildcard $(srcdir)/test/benchmarks/dhrystone/*)
 	$(eval $@_ARCH := $(word 5,$(subst -, ,$@)))
 	$(eval $@_ABI := $(word 6,$(subst -, ,$@)))
@@ -835,34 +836,34 @@ check-dhrystone-linux: $(patsubst %,stamps/check-dhrystone-linux-%,$(GLIBC_MULTI
 
 stamps/check-dhrystone-linux-%: \
 		stamps/build-gcc-linux-stage2 \
-		build-sim \
+		$(SIM_STAMP) \
 		$(wildcard $(srcdir)/test/benchmarks/dhrystone/*)
 	$(eval $@_ARCH := $(word 4,$(subst -, ,$@)))
 	$(eval $@_ABI := $(word 5,$(subst -, ,$@)))
 	$(eval $@_XLEN := $(patsubst rv32%,32,$(patsubst rv64%,64,$($@_ARCH))))
 	$(SIM_PREPARE) $(srcdir)/test/benchmarks/dhrystone/check -march=$($@_ARCH) -mabi=$($@_ABI) -cc=riscv$(XLEN)-unknown-elf-gcc -objdump=riscv$(XLEN)-unknown-elf-objdump -sim=riscv$($@_XLEN)-unknown-elf-run -out=$@ $(filter %.c,$^) || true
 
-stamps/check-binutils-newlib: stamps/build-gcc-newlib-stage2 build-sim stamps/build-dejagnu
+stamps/check-binutils-newlib: stamps/build-gcc-newlib-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-binutils-newlib check-binutils check-gas check-ld -k "RUNTESTFLAGS=--target_board='$(NEWLIB_TARGET_BOARDS)'" || true
 	date > $@
 
-stamps/check-binutils-newlib-nano: stamps/build-gcc-newlib-stage2 build-sim stamps/build-dejagnu
+stamps/check-binutils-newlib-nano: stamps/build-gcc-newlib-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-binutils-newlib check-binutils check-gas check-ld -k "RUNTESTFLAGS=--target_board='$(NEWLIB_NANO_TARGET_BOARDS)'" || true
 	date > $@
 
-stamps/check-binutils-linux: stamps/build-gcc-linux-stage2 build-sim stamps/build-dejagnu
+stamps/check-binutils-linux: stamps/build-gcc-linux-stage2 $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-binutils-linux check-binutils check-gas check-ld -k "RUNTESTFLAGS=--target_board='$(GLIBC_TARGET_BOARDS)'" || true
 	date > $@
 
-stamps/check-gdb-newlib: stamps/build-gcc-newlib-stage2 stamps/build-gdb-newlib build-sim stamps/build-dejagnu
+stamps/check-gdb-newlib: stamps/build-gcc-newlib-stage2 stamps/build-gdb-newlib $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gdb-newlib check-gdb -k "RUNTESTFLAGS=--target_board='$(NEWLIB_TARGET_BOARDS)'" || true
 	date > $@
 
-stamps/check-gdb-newlib-nano: stamps/build-gcc-newlib-stage2 stamps/build-gdb-newlib build-sim stamps/build-dejagnu
+stamps/check-gdb-newlib-nano: stamps/build-gcc-newlib-stage2 stamps/build-gdb-newlib $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gdb-newlib check-gdb -k "RUNTESTFLAGS=--target_board='$(NEWLIB_NANO_TARGET_BOARDS)'" || true
 	date > $@
 
-stamps/check-gdb-linux: stamps/build-gcc-linux-stage2 stamps/build-gdb-linux build-sim stamps/build-dejagnu
+stamps/check-gdb-linux: stamps/build-gcc-linux-stage2 stamps/build-gdb-linux $(SIM_STAMP) stamps/build-dejagnu
 	$(SIM_PREPARE) $(MAKE) -C build-gdb-linux check-gdb -k "RUNTESTFLAGS=--target_board='$(GLIBC_TARGET_BOARDS)'" || true
 	date > $@