va: allocator: Fix translation of VADRMPRIMESurfaceDescriptor
VADRMPRIMESurfaceDescriptor structure describes the offsets from the point of view of the specific handle (DMABuf). While GstVideoInfo (and the meta) describes offsets from the point of the view of the GstBuffer, an aggregate of all the GstMemory (1 per handle).
This changes combined with Mesa Fix fixes decoding failure with AMD driver.
Fixes #1223 (closed)