[media] msi3101: check I/O return values on stop streaming

Coverity CID 1196496: Unchecked return value (CHECKED_RETURN)

Calling "msi3101_ctrl_msg" without checking return value (as is done
elsewhere 8 out of 10 times).

Reported-by:  <scan-admin@coverity.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>