power: qpnp-smbcharger: Add support for dpdm pulsing

The charger for msm8996 doesn't support HVDCP detection
by default. It depends on usb driver for dpdm pulsing,
set the dpdm property so that usb driver can initiate pulsing.

Change-Id: Ib2561f0429338375982dafbf8e71fd2d7ad32ef0
Signed-off-by: Kavya Nunna <knunna@codeaurora.org>