power: qpnp-smb2: Add a DT property to disable USB power-delivery (PD)

Platforms where the USB PHY is not enabled to support USB PD, the
PD support from PMIC can be disabled.

Change-Id: Ibc69700642c48d17c0dc54361fb1e0c011d572ae
Signed-off-by: Anirudh Ghayal <aghayal@codeaurora.org>