UPSTREAM: [CP] Remove unnecessary null check in CreateBuffer

null data is handled in next function call, no need check here.
(cherry picked from commit d148493083aa224d86b3af9699bcb06c727b4426
  https://github.com/intel/media-driver )

BUG=b:378382978
TEST=emerge-${BOARD} libva-intel-media-driver
     vainfo loads iHD driver

Cq-Depend: chromium:5960777, chromium:5960644, chrome-internal:7767917
Change-Id: I8fb87bdab4b60e03f50b2a1aa6bd547ae059c2b4
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/libva-intel-media-driver/+/6057010
Tested-by: Ilja Friedel <ihf@chromium.org>
Commit-Queue: Ilja Friedel <ihf@chromium.org>
Tested-by: Natarajan Balamurugan <balamurugan.natarajan@intel.corp-partner.google.com>
Reviewed-by: Ilja Friedel <ihf@chromium.org>
Reviewed-by: Jao-ke Chin-Lee <jchinlee@google.com>