[PATCH] ioremap balanced with iounmap for drivers/video/atafb

ioremap must be balanced by an iounmap and failing to do so can result in a
memory leak.

Signed-off-by: Amol Lad <amol@verismonetworks.com>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>