[media] saa7134: fix WARN_ON during resume

Do not attempt to reload the tuner modules when resuming after a suspend.
This triggers a WARN_ON in kernel/kmod.c:148 __request_module.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=69581

.

This has always been wrong, but it was never noticed until the WARN_ON
was added in 3.9.

Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Cc: stable@vger.kernel.org      # for v3.9 and up
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>