regulator: qpnp-labibb: Fix LAB PS_CTL configuration for pmi8998

PMI8998 LAB pulse skip configuration is different from PMI8996
and earlier PMICs. Fix it by using the right configuration API
to configure LAB PS_CTL along with supporting PM660A properly.

Since the existing LAB PS configuration threshold for pmi8998 is
incorrect in device tree, update it along with this change.

Change-Id: I2686733867ec3e2909d0c071a5881d3d824c713e
Signed-off-by: Subbaraman Narayanamurthy <subbaram@codeaurora.org>