USB: EHCI: msm: Add snapshot of HSIC Host Controller

This snapshot is taken from msm-3.10 commit f62f95b715a5
(Merge "dwc3-msm: Turn on 1.8V LDO before turning on 3.3V LDO").

This patch adds support for EHCI compliant USB Host Controller
present in MSM chips. This Controller uses an HSIC PHY which
communicates with downstream devices using STROBE/DATA lines.

HSIC is a supplement to USB 2.0 specification and is preferred
for chip-to-chip interconnect (having maximum circuit length of
10cm) as it removes the analog transceivers.

Change-Id: I61ad262eb4f925174cb3a1de240f396e3f2fcb50
Signed-off-by: Jack Pham <jackp@codeaurora.org>