i965_encoder: remove double check for VAStatus result
i965_encoder: remove double check for VAStatus result

after creating underlying surface there's a double check on the
VAStatus result. Replace it with ASSERT_RET.

Signed-off-by: Daniel Charles <9f8d44a34cf25995df1daf4e48c6fa87b67d5dc5@intel.com>
Reviewed-by: Sean V Kelley <2e220d3765e3e059981b3c8d241463f952b3ee5f@posteo.de>
(cherry picked from commit c237791816a1e1067fc5504401a95ae910daa950)

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