WLAN has a requirement to trigger a PBS sequence for XO calibration
for factory testing. To support this, expose a new register under
PMK8550 SDAM2 for clients to write input data into and a new PBS
regulator on which clients can vote to trigger the PBS sequence.
Change-Id: Ia314c8cba7a6205943b99e7530990ea6dde8b09c
Signed-off-by: Kamal Wadhwa <quic_kamalw@quicinc.com>