USB: msm_otg: Add support for new ioctl for voltage request

Add support for new ioctls for userspace to let kernel driver
know about new voltage request being negogiated and also result
whether the request is successful or not, when HVDCP charger is
connected.

Change-Id: Ie7271cc2dea082ceb33d67f0b4d2959ed977b618
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>