neofb: drop redundant code

Drop structure which is only set but never read.  Drop variables which are
only set and never read.  Convert one long switch into two shorter ones.

Add cpu_relax() in busy waiting loop.

Signed-off-by: Krzysztof Helt <krzysztof.h1@wp.pl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>