staging: xgifb: vb_setmode: fix long line warnings

Fix a number of checkpatch warnings in xgfib/vb_setmode.c about line
length being over 80 characters.

Signed-off-by: Kenny Ballou <kballou@devnulllabs.io>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>