usb: dwc3-msm: Add support for voltage_max power supply property
usb: dwc3-msm: Add support for voltage_max power supply property

Allow voltage_max property to be written from user space.  The USB
power supply input voltage can be limited by writing into
/sys/class/power_supply/usb/voltage_max sysfs file.  The user space
charger detection application uses this property value to place
an appropriate voltage request to the charger.

Change-Id: Ifefc87fb01d64850fcce6098d274e524bcaaa697
Signed-off-by: Pavankumar Kondeti <e4a0348e45a0df0ba79f6b06c66df8ae7aca44a4@codeaurora.org>

TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas