sim: ppc: delete unused build compile & link settings

These should have been removed as part of the ppc/igen merging into the
top-level, but they were missed.  Clean up now.

sim/ppc/Makefile.in

@@ -84,12 +84,9 @@ SIM_FPU_CFLAGS = -DHAVE_COMMON_FPU -I../common -I${srcdir}/../common
 
 STD_CFLAGS	= $(CFLAGS) $(WERROR_CFLAGS) $(INLINE_CFLAGS) $(CONFIG_CFLAGS) $(WARN_CFLAGS) $(INCLUDES) $(INCGNU) $(SIM_FPU_CFLAGS)
 NOWARN_CFLAGS	= $(CFLAGS) $(INLINE_CFLAGS) $(CONFIG_CFLAGS) $(INCLUDES) $(SIM_FPU_CFLAGS)
-BUILD_CFLAGS	= $(CFLAGS_FOR_BUILD) $(INCLUDES) $(WARN_CFLAGS)
 
 LIBS = $(COMMON_LIBS) @LIBS@ $(LIBGNU) $(LIBGNU_EXTRA_LIBS)
 
-LINK_FOR_BUILD = $(CC_FOR_BUILD) $(BUILD_CFLAGS) $(LDFLAGS_FOR_BUILD) -o $@
-
 IGEN_OPCODE_RULES = @sim_opcode@
 IGEN_DECODE_MECHANISM = @sim_decode_mechanism@
 IGEN_DUPLICATE = @sim_dup@