[XFS] Update the MAINTAINERS file entry for XFS - change git repo name.

Make the git repository bare and so give it the conventional .git suffix.
Signed-off-by: Tim Shimmin <tes@sgi.com>

MAINTAINERS

@@ -4026,7 +4026,7 @@ P:	Tim Shimmin
 M:	xfs-masters@oss.sgi.com
 L:	xfs@oss.sgi.com
 W:	http://oss.sgi.com/projects/xfs
-T:	git git://oss.sgi.com:8090/xfs/xfs-2.6
+T:	git git://oss.sgi.com:8090/xfs/xfs-2.6.git
 S:	Supported
 
 XILINX UARTLITE SERIAL DRIVER