-gpu: Add implicit (and default) sync mechanism
for blobs
=== TEST SCRIPT BEGIN ===
#!/bin/bash
git rev-parse base > /dev/null || exit 0
git config --local diff.renamelimit 0
git config --local diff.renames True
git config --local diff.algorithm histogram
./scripts/checkpatch.pl --mailback b
When the Guest and Host are using Blob resources, there is a chance
that they may use the underlying storage associated with a Blob at
the same time leading to glitches such as flickering or tearing.
To prevent these from happening, the Host needs to ensure that it
waits until its Blit is completed
