Revert "Add a reference to ucounts for each cred"

This reverts commit b2c4d9a33c which is
commit 905ae01c4a upstream.

This commit should not have been applied to the 5.10.y stable tree, so
revert it.

Reported-by: "Eric W. Biederman" <ebiederm@xmission.com>
Link: https://lore.kernel.org/r/87v93k4bl6.fsf@disp2133
Cc: Alexey Gladkov <legion@kernel.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kernel/user_namespace.c

@@ -1340,9 +1340,6 @@ static int userns_install(struct nsset *nsset, struct ns_common *ns)
 	put_user_ns(cred->user_ns);
 	set_cred_user_ns(cred, get_user_ns(user_ns));
 
-	if (set_cred_ucounts(cred) < 0)
-		return -EINVAL;
-
 	return 0;
 }