V4L/DVB (3426): PATCH cx88-mpeg: cx8802_restart_queue() for blackbird

Fixes "cx8802_restart_queue: queue is empty" storm in syslog

Signed-off-by: Jelle Foks <jelle@foks.8m.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>