CHROMIUM: uvcvideo: Handle status_start while status_stop is in progress.

CHROMIUM: uvcvideo: Handle status_start while status_stop is in progress.

While usb_kill_urb is in progress, calls to usb_submit_urb will fail
with -EPERM (documented in Documentation/usb/URB.txt). The UVC driver
does not correctly handle this case -- there is no synchronization
between uvc_v4l2_open / uvc_status_start and uvc_v4l2_release /
uvc_status_stop.

This patch adds a retry / timeout when uvc_status_open / usb_submit_urb
returns -EPERM. This usually means that usb_kill_urb is in progress, and
we just need to wait a while.

BUG=chromium:226216
TEST=Manual. Repeat suspend / resume on Stout many times, verify that
open() on /dev/video0 never fails.

Change-Id: I8a69dab345a18c89e175bd916aa943edd080b6cc
Signed-off-by: Shawn Nematbakhsh <shawnn@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/48982
Reviewed-by: Vincent Palatin <vpalatin@chromium.org>