esoc: Use qpnp-power-on apis to reset modem

In recent targets a PON device can reset the attached modem chip via
its primary pmic using SPMI. Integrate apis to do a warm reset for
modem making sure we are still backwards comaptible.

Change-Id: I29e797d9c5162c397e38a2fa73182eb63dbe36e5
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>