Makefile: update check-docs target

When we added bunch of git-remote-* helper backends, we should have
done this to squelch complaints that they do not have their own
manual pages.  Also the entry for git-remote-helpers was not
properly marked as a non-command.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

Makefile

@@ -2103,6 +2103,7 @@ check-docs::
 		git-merge-octopus | git-merge-ours | git-merge-recursive | \
 		git-merge-resolve | git-merge-subtree | \
 		git-fsck-objects | git-init-db | \
+		git-remote-* | git-stage | \
 		git-?*--?* ) continue ;; \
 		esac ; \
 		test -f "Documentation/$$v.txt" || \
@@ -2141,7 +2142,7 @@ check-docs::
 		documented,gittutorial | \
 		documented,gittutorial-2 | \
 		documented,git-bisect-lk2009 | \
-		documented.git-remote-helpers | \
+		documented,git-remote-helpers | \
 		documented,gitworkflows | \
 		sentinel,not,matching,is,ok ) continue ;; \
 		esac; \