media: usbtv: Fix refcounting mixup

commit bf65f8aabdb37bc1a785884374e919477fe13e10 upstream.

The premature free in the error path is blocked by V4L
refcounting, not USB refcounting. Thanks to
Ben Hutchings for review.

[v2] corrected attributions

Signed-off-by: Oliver Neukum <oneukum@suse.com>
Fixes: 50e704453553 ("media: usbtv: prevent double free in error case")
CC: stable@vger.kernel.org
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>