msm: qpnp-haptic: add PON regulator support

Add PON regulator support in order to set the spare
register bit of the PON peripheral. Haptics enables
the regulator when the module is in use and then
disables it when it is done.

Change-Id: I3ecfe3cbb12799089d4fdd4b07c7c84afb80e173
Signed-off-by: Alex Sarraf <asarraf@codeaurora.org>