blue-common: Use custom gralloc_priv to make cam HAL happy.

Camera HAL was compiled against CAF tag <need to look it up>,
which has extra members in private_handle_t.  The fd_metadata
member shifts the cam HAL's size/offset up by 4 bytes.

Since cam HAL only uses fd, size, and offset, and fd is not
shifted, move bufferType up two slots so that size/offset are
aligned.  Adreno blobs don't use any of the three items that
are moving, and everything else is compiled.

Also enable -DMR0_CAMERA_BLOB for cam blob compatibility

Change-Id: I56614aedebe749cabeda62ac658363a6f1a8311c