[PATCH] savagefb iomem annotations

trivial iomem annotations + memset() replaced with memset_io() in a
place that deals with ioremapped area. 

Signed-off-by: Al Viro <viro@parcelfarce.linux.theplanet.co.uk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>