linux-phytec-ti

mfd: Support additional parent IDs for wm831x

Some newer device revisions add a second parent ID. Support this in
the device validity checks done at startup.

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@kernel.org
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>