With the introduction of an additional mutex class member, the name of the existing one is too generic. Rename CameraDevice::mutex_ in CameraDevice::descriptorsMutex_ and use the libcamera provided libcamera::Mutex type to align the style with the rest of the code base. Signed-off-by: Jacopo Mondi <jacopo@jmondi.org> Reviewed-by: Niklas Söderlund <niklas.soderlund@ragnatech.se> Reviewed-by: Hirokazu Honda <hiroh@chromium.org> Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>