6648 illumos build should be explicit about C standards

*** 81,92 ****
  
  #
  # Create assym.h
  #
  $(GENASSYM): $(GENASSYM_SRC)
!         $(NATIVECC) $(ALWAYS_DEFS) $(GENASSYM_DEFS) $(NATIVE_INC_PATH) \
!            -o $@ $(GENASSYM_SRC)
  
  $(ASSYM_H): $(OFFSETS_SRC) $(PLATFORM_OFFSETS_SRC) $(GENASSYM)
          $(OFFSETS_CREATE) <$(OFFSETS_SRC) >$@
          $(OFFSETS_CREATE) <$(PLATFORM_OFFSETS_SRC) >>$@
          $(GENASSYM) >>$@
--- 81,92 ----
  
  #
  # Create assym.h
  #
  $(GENASSYM): $(GENASSYM_SRC)
!         $(NATIVECC) $(NATIVE_CFLAGS) $(ALWAYS_DEFS) $(GENASSYM_DEFS) \
!            $(NATIVE_INC_PATH) -o $@ $(GENASSYM_SRC)
  
  $(ASSYM_H): $(OFFSETS_SRC) $(PLATFORM_OFFSETS_SRC) $(GENASSYM)
          $(OFFSETS_CREATE) <$(OFFSETS_SRC) >$@
          $(OFFSETS_CREATE) <$(PLATFORM_OFFSETS_SRC) >>$@
          $(GENASSYM) >>$@