Merge branch 'mk/make-rm-depdirs-could-be-empty'

"make COMPUTE_HEADER_DEPENDENCIES=no clean" would try to run "rm -rf $(dep_dirs)" with an empty dep_dir, but some implementations of "rm -rf" barf on an empty argument list. * mk/make-rm-depdirs-could-be-empty: Makefile: don't run "rm" without any files

Author: gitster

Makefile

@@ -2449,8 +2449,7 @@ clean: profile-clean
 builtin/*.o $(LIB_FILE) $(XDIFF_LIB) $(VCSSVN_LIB)
 $(RM) $(ALL_PROGRAMS) $(SCRIPT_LIB) $(BUILT_INS) git$X
 $(RM) $(TEST_PROGRAMS)
-$(RM) -r bin-wrappers
-$(RM) -r $(dep_dirs)
+$(RM) -r bin-wrappers $(dep_dirs)
 $(RM) -r po/build/
 $(RM) *.spec *.pyc *.pyo */*.pyc */*.pyo common-cmds.h $(ETAGS_TARGET) tags cscope*
 $(RM) -r $(GIT_TARNAME) .doc-tmp-dir