ppc4xx: Add AMCC Glacier 406GT eval board support

This patch adds support for the AMCC Glacier 460GT eval board.
The main difference to the Canyonlands board are listed here:

- 4 ethernet ports instead of 2
- no SATA port
- no USB port

Currently EMAC2+3 are not working. This will be fixed in a later
release.

Signed-off-by: Stefan Roese <sr@denx.de>
diff --git a/MAINTAINERS b/MAINTAINERS
index e31ea06..d9ffebf 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -322,6 +322,7 @@
 	bunbinga		PPC405EP
 	canyonlands		PPC460EX
 	ebony			PPC440GP
+	glacier			PPC460GT
 	haleakala		PPC405EXr
 	katmai			PPC440SPe
 	kilauea			PPC405EX