Rename ALLPPUDIR to ALLPPUDIRS to use same make variable as in packages and utils directories

compiler/Makefile.fpc

@@ -1280,7 +1280,7 @@ rtlinstall:
 #####################################################################
 
 PPUDIR=$(COMPILER_UNITTARGETDIR)
-ALLPPUDIR=$(CPU_TARGET)/units/*
+ALLPPUDIRS:=$(wildcard $(CPU_TARGET)/units/*)
 PPULIST=$(wildcard $(PPUDIR)/*.ppu)
 PPULOGLIST=$(subst .ppu,.log-ppu,$(PPULIST))
 
@@ -1306,6 +1306,7 @@ vpath %.log-ppu $(PPUDIR) $(RTLPPUDIR) $(ALLPPUDIR)
 	$(MAKE) -C $(COMPILERUTILSDIR) ppudump$(EXEEXT)
 
 ppuinfo :
+	echo list of PPU directories is "$(ALLPPUDIRS)"
 	echo PPU list is "$(PPULIST)"
 	echo PPULOG list is "$(PPULOGLIST)"
 	echo RTLPPUDIR is "$(RTLPPUDIR)"