USB: EHCI: msm: Add support for EHCI based Host Controller

This patch adds support for EHCI compliant USB Host Controller
for Liquid on 8064.
This driver supports Host only mode and is different from ehci-msm
which relies on OTG driver for putting hardware in low pwer mode
and PHY initialization as well.

Change-Id: I84b63b2577311900a0b434f53df547bad62f6316
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>