tty: serial: msm_geni_serial: Add UART Console Port PM state callback

UART Console Port PM callback enables the console driver to turn on
and turn off the resources at appropriate time. This enables the
console driver to be in sync with the UART framework with respect to
the power states.

CRs-Fixed: 2112282
Change-Id: I8726be891926c5cef6280c007306c3f7cd79c2c2
Signed-off-by: Karthikeyan Ramasubramanian <kramasub@codeaurora.org>