usb: ci13xxx_msm_hsic: Add support to use GDSC regulator

On newer platforms, GDSC supply is being used to power up HSIC
core. Hence add supports to use gdsc regulator with HSIC peripheral.

Change-Id: Id910e001fe6b2a962f537ce64a9817036a5a3c59
Signed-off-by: Mayank Rana <mrana@codeaurora.org>