media: airspy: Return queued buffers on start_streaming() failure

In the Linux kernel, the following vulnerability has been resolved: media: airspy: Return queued buffers on start_streaming() failure The vb2 framework hands buffers to the driver via buf_queue() before calling start_streaming(). If start_streaming() returns an error without first returning those buffers via vb2_buffer_done(), vb2_start_streaming() fires WARN_ON(owned_by_drv_count) and the queued buffers leak. airspy_start_streaming() returned -ENODEV early when the USB device had been disconnected (s->udev == NULL) without returning any buffers that buf_queue() had already accepted. Take v4l2_lock first and jump to the existing err_clear_bit label, which already drains s->queued_bufs via vb2_buffer_done(..., VB2_BUF_STATE_QUEUED) before unlocking. This mirrors the uvcvideo fix in commit 4cf3b6fd54eb ("media: uvcvideo: Return queued buffers on start_streaming() failure").