[media] rc/nuvoton_cir: fix locking issue when calling nvt_disable_cir

nvt_disable_cir calls nvt_disable_logical_dev (that may sleep) and is
called from contexts holding a spinlock.
Fix this and remove the unneeded clearing of CIR_IREN as this is done
in nvt_cir_disable already.

Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@osg.samsung.com>