V4L/DVB (6247): Fix bug #8689: Fixes IR stop/start during suspend/resume

IR workqueue should be disabled during suspend. This avoids some troubles, like
the one reported on bug #8689:

"The Hauppauge HVR 1100 ir-remote control does not work after resume from
suspend to ram or disk."

This patch disables IR before suspending, re-enabling it after resume.

Thanks to Peter Poklop <Peter.Poklop@gmx.at> for reporting it and helping with
the fix.

Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Reviewed-by: Peter Poklop <Peter.Poklop@gmx.at>