fbdev: s1d13xxxfb: add accelerated bitblt functions

Add accelerated bitblt functions to s1d13xxx based video chipsets, more
specificly functions copyarea and fillrect.

It has only been tested and activated for 13506 chipsets but is expected
to work for the majority of s1d13xxx based chips.  This patch also cleans
up the driver with respect of whitespaces and other formatting issues.  We
update the current status comments.

[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Kristoffer Ericson <kristoffer.ericson@gmail.com>
Cc: Russell King <rmk@arm.linux.org.uk>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>