[PATCH] Clarify T: field in MAINTAINERS

Pavel Machek points out that for git repos, what we include is not
actually a URL.  It is undesirable to use a URL since git repos can be
accessed in many different ways.

Signed-off-by: Jody McIntyre <scjody@steamballoon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>