viafb: remove duplicated mode information

Remove the mode information from viafbdev.c and uses the one of viamode.c
instead.  This is possible because horizontal and vertical address are the
same as horizontal and vertical resolution.  The reduced blanking modes in
the table are no problem because they have a higher index than the normal
modes and therefore always the normal modes are selected just as the old
behaviour.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Cc: Scott Fang <ScottFang@viatech.com.cn>
Cc: Joseph Chan <JosephChan@via.com.tw>
Cc: Harald Welte <laforge@gnumonks.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>