usb: phy: Add snapshot of USB QUSB PHY v2 driver

This change adds USB QUSB PHY v2 driver to configure USB QUSB PHY
having major revision version as 2. This snapshot is taken as of
msm-4.4 commit 38c509c5664e ("ARM: dts: msm: Change pinctrl settings
for BLSP1 UART3 for msmcobalt").

It fixes compilation issue by using relevant available API with
msm-3.18 kernel.
1. use msm specific clk_reset() API instead of upstream kernel based
reset clock framework APIs
2. use regulator_set_optimum_mode() API instead of regulator_set_load()
API

CRs-Fixed: 1083141
Change-Id: Iee6b58e9d1b4c6021b33814b3ee3e22b6a8c672e
Signed-off-by: Mayank Rana <mrana@codeaurora.org>