rtc: qpnp-rtc: Add module parameter to control power-on alarm

Power-on alarm feature can be enabled/disabled by writing 1/0
to the module parameter exported by driver.

CRs-Fixed: 432312
Change-Id: I2a2337adb2ddc186ec312648b11b6a35ea698856
Signed-off-by: Ashay Jaiswal <ashayj@codeaurora.org>