regulator: qpnp: Add property to override type registers

On some regulator hardware, the values read on SPMI offset 0x4 (type)
and 0x5 (subtype) are incorrect. Add a new optional property called
qcom,force-type that allows a user to override the hardware values
with values supplied in the Device Tree.

Change-Id: Id73fe69873f5dc9d0f2623771872aa2eaddd66f1
Signed-off-by: Michael Bohan <mbohan@codeaurora.org>