Revert "ARM: dts: msm: set APC supply ncp6335d regulator to PWM mode for msm8926"

This reverts commit 2edf4c40.

As CPR is disabled due to stability issues, the Onsemi NCP6335D regulator
will not trigger an interrupt storm from the CPR controller even if it's
operating in AUTO mode.

Change-Id: Ic873bfe3f87ea23eb5499beadb3905ad2a7da72f
Signed-off-by: Ke Liu <keliu@codeaurora.org>