CHROMIUM: s5p-mfc: enable NV12M/NV21M decoder output.

CHROMIUM: s5p-mfc: enable NV12M/NV21M decoder output.

These two formats work on hardware; there is no need to disable them.
Enable them so we can have linear multiplanar YUV output support.

Signed-off-by: John Sheu <sheu@google.com>
BUG=chromium-os:38376
BUG=chromium:167417
TEST=local build, run on snow
Change-Id: Ic4889ca26555b067e7faadf9027e789633622dee
Reviewed-on: https://gerrit.chromium.org/gerrit/42761
Reviewed-by: Pawel Osciak <posciak@chromium.org>
Tested-by: John Sheu <sheu@chromium.org>
Commit-Queue: John Sheu <sheu@chromium.org>