Also define CPU_clean make targets for CPUs not yet in CYCLETARGETS, like mips64 now

compiler/Makefile.fpc

@@ -674,6 +674,7 @@ endif
 PPC_TARGETS=i386 m68k powerpc sparc arm armeb x86_64 powerpc64 mips mipsel mips64 mips64el avr jvm i8086 aarch64 sparc64 riscv32 riscv64 xtensa z80 wasm32
 PPC_SUFFIXES=386 68k ppc sparc arm armeb x64 ppc64 mips mipsel mips64 mips64el avr jvm 8086 a64 sparc64 rv32 rv64 xtensa z80 wasm32
 INSTALL_TARGETS=$(addsuffix _exe_install,$(sort $(CYCLETARGETS) $(PPC_TARGETS)))
+CLEAN_TARGETS=$(addsuffix _clean,$(sort $(CYCLETARGETS) $(PPC_TARGETS)))
 SYMLINKINSTALL_TARGETS=$(addsuffix _symlink_install,$(sort $(CYCLETARGETS) $(PPC_TARGETS)))
 
 .PHONY: $(PPC_TARGETS) $(INSTALL_TARGETS)$(SYMLINKINSTALL_TARGETS)
@@ -736,7 +737,7 @@ execlean :
 	-$(DEL) $(EXENAME) $(TEMPWPONAME1) $(TEMPWPONAME2) $(ALL_G_COMPILERS)
 	-$(DEL) fpcmade.generate_g_compilers
 
-$(addsuffix _clean,$(ALLTARGETS)):
+$(CLEAN_ALLTARGETS):
         -$(DELTREE) $(addprefix $(subst _clean,,$@),/units)
         -$(DELTREE) $(addprefix $(subst _clean,,$@),/bin)
         -$(DEL) $(addprefix $(subst _clean,,$@)/,*$(OEXT) *$(PPUEXT) *$(RSTEXT) *$(ASMEXT) *$(STATICLIBEXT) *$(SHAREDLIBEXT) *$(PPLEXT))