Directory.mk: The subdirectories' clean and distclean targets need to be
unique to avoid the "overriding recipe for target"  warning.
@@ -42,6 +42,7 @@ CONFIGSUBDIRS := $(filter-out $(dir $(wildcard *$(DELIM)Kconfig)),$(SUBDIRS))
CLEANSUBDIRS := $(dir $(wildcard *$(DELIM).built))
CLEANSUBDIRS += $(dir $(wildcard *$(DELIM).depend))
CLEANSUBDIRS += $(dir $(wildcard *$(DELIM).kconfig))
+CLEANSUBDIRS := $(sort $(CLEANSUBDIRS))
all: nothing
