ASoC: sm8150: change of_property_read_bool to type u32

of_property_read_bool prevents an overlay to set it false
as /delete-property/ is not supported in device tree overlay.
Use of_property_read_u32 to read property to allow it to
be changed in overlay device tree.

Change-Id: Ic1ae38d99999b3ff7e268a6360d55fc2624c0b6f
Signed-off-by: Sudheer Papothi <spapothi@codeaurora.org>