codec2: unlock GraphicBuffer if lockYCbCr succeeded but could not process it

We may be able to lockYCbCr a graphic buffer and not understand it
(e.g. stride could be invalid). Unlock it before trying to relock using
lock().

Bug: 190459461
Change-Id: I916381cd04a4ff2180b9052a9a58d9092412e932
1 file changed