mm-video-v4l2: venc: update allocation-size check for meta-buffer

Metadata buffer |MetadataBufferType|buffer_handle_t| size can be
8 or 16 bytes on 32-bit or 64-bit respectively. Update the check
which always assumes 32-bit size.

bug: 22487196
Change-Id: Iab161ed455a6ea2842116c89b2e389cdccf867b8
1 file changed