t5510: Do not use $(pwd) when fetching / pushing / pulling via rsync

On MINGW, "pwd" is defined as "pwd -W" in test-lib.sh. This usually is the
right thing, but the absolute Windows path with a colon confuses rsync. We
could use $PWD in this case to work around the issue, but in fact there is
no need to use an absolute path in the first place, so get rid of it.

This was discovered in the context of the mingwGitDevEnv project and only
did not surface before with msysgit because the latter does not ship
rsync.

Signed-off-by: Sebastian Schuberth <sschuberth@gmail.com>
Acked-by: Johannes Schindelin <Johannes.Schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

t/t5510-fetch.sh

@@ -301,7 +301,7 @@ test_expect_success 'fetch via rsync' '
 	mkdir rsynced &&
 	(cd rsynced &&
 	 git init --bare &&
-	 git fetch "rsync:$(pwd)/../.git" master:refs/heads/master &&
+	 git fetch "rsync:../.git" master:refs/heads/master &&
 	 git gc --prune &&
 	 test $(git rev-parse master) = $(cd .. && git rev-parse master) &&
 	 git fsck --full)
@@ -312,7 +312,7 @@ test_expect_success 'push via rsync' '
 	(cd rsynced2 &&
 	 git init) &&
 	(cd rsynced &&
-	 git push "rsync:$(pwd)/../rsynced2/.git" master) &&
+	 git push "rsync:../rsynced2/.git" master) &&
 	(cd rsynced2 &&
 	 git gc --prune &&
 	 test $(git rev-parse master) = $(cd .. && git rev-parse master) &&
@@ -323,7 +323,7 @@ test_expect_success 'push via rsync' '
 	mkdir rsynced3 &&
 	(cd rsynced3 &&
 	 git init) &&
-	git push --all "rsync:$(pwd)/rsynced3/.git" &&
+	git push --all "rsync:rsynced3/.git" &&
 	(cd rsynced3 &&
 	 test $(git rev-parse master) = $(cd .. && git rev-parse master) &&
 	 git fsck --full)