linux-imx

viafb: avoid refresh and mode lookup in set_par

As check_var already ensures that the mode is valid there is no need
to do those expensive lookups here again. The only thing that might
change is that the deprecated interface could report slightly
different refresh rates due to rounding errors.

Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>