git-submodule.sh: fix '/././' path normalization

When we add a new submodule the path of the submodule is being
normalized. We fail to normalize multiple adjacent '/./', though.
Thus 'path/to/././submodule' will become 'path/to/./submodule' where
it should be 'path/to/submodule' instead.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Acked-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/t/t7400-submodule-basic.sh b/t/t7400-submodule-basic.sh
index c28e8d8..4004d12 100755
--- a/t/t7400-submodule-basic.sh
+++ b/t/t7400-submodule-basic.sh
@@ -171,6 +171,23 @@
 	test_cmp empty untracked
 '
 
+test_expect_success 'submodule add with /././ in path' '
+	echo "refs/heads/master" >expect &&
+	>empty &&
+
+	(
+		cd addtest &&
+		git submodule add "$submodurl" dotslashdotsubmod/././frotz/./ &&
+		git submodule init
+	) &&
+
+	rm -f heads head untracked &&
+	inspect addtest/dotslashdotsubmod/frotz ../../.. &&
+	test_cmp expect heads &&
+	test_cmp expect head &&
+	test_cmp empty untracked
+'
+
 test_expect_success 'submodule add with // in path' '
 	echo "refs/heads/master" >expect &&
 	>empty &&