Input: twl6040-vibra: Check the selected path for vibra

The VIBSELL/R bit in the VIBCTLL/R register tells the source of the data,
which is going to be used to drive the attached motor(s).
Do not allow effect execution if any of the channels are set to receive
audio data.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Acked-by: Dmitry Torokhov <dtor@mail.ru>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>