power: pm8921-charger: fix the order of forcing 19.2Mhz and exit LPM

Switching out of LPM before forcing 19.2Mhz can cause the PMIC to
lockup causing the PMIC to not trigger usb insertion interrupts while
asleep.

The charger is switched to LPM while the apps is suspended. LPM means
that when a charger is plugged in the charger runs from 19.2Mhz or 32Khz
based on sleep bar. When a charger is absent it runs of 32Khz regardless
of sleep bar.

An issue was observed where USB insertion was not detected and the
device continued to be in suspend state. Upon a subsequent wakeup
from pwr key or any other interrupt, it will detect usb insertion.

Switching the order of exiting LPM and forcin 19.2Mhz in the resume path
fixes the lockups. The root cause was that the charger was locked up
already in a previous resume and so did not respond to the usb insertions.

Change-Id: I365b505858e59d647ff49f8bb3c06fbfef2f7328
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>