[PATCH] tgafb: sync-on-green support fixes

This sets up the deep register of the TGA ASIC as well as the blank pedestal
of the Bt463 RAMDAC correctly for the sync-on-green mode.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
Cc: James Simmons <jsimmons@infradead.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>