Back out aix makefile patch.

Author: bmomjian

src/makefiles/Makefile.aix

@@ -24,10 +24,6 @@ POSTGRES_IMP= postgres$(IMPSUFF)
 
 MKLDEXPORT=$(top_srcdir)/src/backend/port/aix/mkldexport.sh
 
-.PHONY: default_aix
-
-default_aix: all
-
 $(POSTGRES_IMP):
 	@echo Making $@
 	$(MKLDEXPORT) postgres $(bindir) > $@