add topgit for T: in MAINTAINERS doc.

Hi us,
When i see MAINTAINERS, i didn't find topgit in T:. It only reads that "T: SCM tree type and location. Type is one of: git, hg, quilt, stgit." But there is topgit used in MAINTAINERS doc like following.

ARM/EZX SMARTPHONES (A780, A910, A1200, E680, ROKR E2 and ROKR E6)
M: Daniel Ribeiro <[email protected]>
M: Stefan Schmidt <[email protected]>
M: Harald Welte <[email protected]>
L: [email protected] (subscribers-only)
W: http://www.openezx.org/
S: Maintained
T: topgit git://git.openezx.org/openezx.git
F: arch/arm/mach-pxa/ezx.c
My patcher like following.

---
 MAINTAINERS |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)

index 95ac55c..3b4c67a 100644
@@ -72,7 +72,7 @@ Descriptions of section entries:
 	L: Mailing list that is relevant to this area
 	W: Web-page with status/info
 	Q: Patchwork web based patch tracking system site
-	T: SCM tree type and location.  Type is one of: git, hg, quilt, stgit.
+	T: SCM tree type and location.  Type is one of: git, hg, quilt, stgit, topgit.
 	S: Status, one of the following:
 	   Supported:	Someone is actually paid to look after this.
 	   Maintained:	Someone actually looks after it.

1.7.0.4