Merge branch 'mm/clean-doc-fix' into maint

The documentation for "git clean" has been corrected; it mentioned
that .git/modules/* are removed by giving two "-f", which has never
been the case.

* mm/clean-doc-fix:
  Documentation/git-clean.txt: don't mention deletion of .git/modules/*

Author: gitster

Documentation/git-clean.txt

@@ -37,9 +37,7 @@ OPTIONS
 	to false, 'git clean' will refuse to delete files or directories
 	unless given -f, -n or -i. Git will refuse to delete directories
 	with .git sub directory or file unless a second -f
-	is given. This affects also git submodules where the storage area
-	of the removed submodule under .git/modules/ is not removed until
-	-f is given twice.
+	is given.
 
 -i::
 --interactive::