fbdev: cleanup of sparc FB options

This patch puts all SBUS/UPA selection under one option "SBUS/UPA
framebuffers" and moves all sparc specific drivers next to them in one group.

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