jpeg/dec: gen8+ set correct fourcc for monochrome decode
jpeg/dec: gen8+ set correct fourcc for monochrome decode

When the jpeg picture params have 1 component the
fourcc needs to be set to VA_FOURCC_Y800.

Signed-off-by: U. Artie Eoff <32aece0d55055227b44d04b7d0051cf3d04ee871@intel.com>
Reviewed-by: Sean V Kelley <2e220d3765e3e059981b3c8d241463f952b3ee5f@posteo.de>

01org/iotg-lin-gfx-va-driver,01org/iotg-lin-gfx-va-driver,01org/iotg-lin-gfx-va-driver,01org/iotg-lin-gfx-va-driver,01org/iotg-lin-gfx-va-driver