staging: xgifb: vb_setmode: delete empty if statement blocks

Delete empty if statement blocks. The patch eliminates following
checkpatch.pl warnings:

WARNING: suspect code indent for conditional statements (8, 8)

Signed-off-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>