V4L: uvcvideo: Don't free URB buffers on suspend

V4L: uvcvideo: Don't free URB buffers on suspend

(cherry picked from commit e01117c81676dc9897f567e32cdc13a26e85280b)

V4L: uvcvideo: Don't free URB buffers on suspend.

All submitted URBs must be killed at suspend time, but URB buffers don't
have to be freed. Avoiding a free on suspend/reallocate on resume lowers
the pressure on system memory.

Signed-off-by: Laurent Pinchart <laurent.pinchart@skynet.be>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>