Add missing makefile dependence

This manifested as a spurious compile warning when using make -j.

Makefile.in

@@ -189,7 +189,7 @@ $(2)_objs := $$(patsubst %.cc, %.o, $$($(2)_srcs))
 $(2)_c_objs := $$(patsubst %.c, %.o, $$($(2)_c_srcs))
 $(2)_deps := $$(patsubst %.o, %.d, $$($(2)_objs))
 $(2)_c_deps := $$(patsubst %.o, %.d, $$($(2)_c_objs))
-$$($(2)_pch) : %.h.gch : %.h
+$$($(2)_pch) : %.h.gch : %.h $$($(2)_gen_hdrs)
 	$(COMPILE) $$<
 # If using clang, don't depend (and thus don't build) precompiled headers
 $$($(2)_objs) : %.o : %.cc $$($(2)_gen_hdrs) $(if $(filter-out clang,$(CC)),$$($(2)_pch))

riscv/riscv.mk.in

@@ -49,7 +49,8 @@ riscv_gen_srcs = \
 	$(addsuffix .cc, $(call get_insn_list,$(src_dir)/riscv/encoding.h))
 
 icache.h:
-	$(src_dir)/riscv/gen_icache 1024 > $@
+	$(src_dir)/riscv/gen_icache 1024 > $@.tmp
+	mv $@.tmp $@
 
 $(riscv_gen_srcs): %.cc: insns/%.h insn_template.cc
 	sed 's/NAME/$(subst .cc,,$@)/' $(src_dir)/riscv/insn_template.cc | sed 's/OPCODE/$(call get_opcode,$(src_dir)/riscv/encoding.h,$(subst .cc,,$@))/' > $@