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

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

Return buffers if streaming fails to start due to uvc_pm_get() error.

This bug may be responsible for a warning I got running

    while :; do yavta -c3 /dev/video0; done

on an xHCI controller which failed under this workload.
I had no luck reproducing this warning again to confirm.

xhci_hcd 0000:09:00.0: HC died; cleaning up
usb 13-2: USB disconnect, device number 2
WARNING: CPU: 2 PID: 29386 at drivers/media/common/videobuf2/videobuf2-core.c:1803 vb2_start_streaming+0xac/0x120

Fixes: 7dd56c47784a ("media: uvcvideo: Remove stream->is_streaming field")
Cc: stable@vger.kernel.org
Signed-off-by: Michal Pecio <michal.pecio@gmail.com>
Reviewed-by: Ricardo Ribalda <ribalda@chromium.org>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patch.msgid.link/20251015133642.3dede646.michal.pecio@gmail.com
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Hans Verkuil <hverkuil+cisco@kernel.org>