ext_external_objects: Remove unnecessary NULL check.
Fix defect reported by Coverity Scan.
Dereference before null check (REVERSE_INULL)
check_after_deref: Null-checking attachments suggests that it may
be null, but it has already been dereferenced on all paths leading
to the check.
Fixes:
8713fbda2 ("ext_external_objects: Vulkan framework additions")
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Tapani Pälli <tapani.palli@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/piglit/-/merge_requests/660>