QCamera2/HAL3: correct mutex lock/unlock sequence

Bug: 36716469
CRs-Fixed: 2053027
Change-Id: I6699c3682eec419fb6efb0583e9909e5739476a0
(cherry picked from commit a5eedde871c8e87784014e541c4aec247e954dc2)
(cherry picked from commit c0610d4f9af107a40b0f57c344e764d2abc84159)
1 file changed