usb: phy: msm: Select secondary PHY via TCSR

Select the secondary PHY using the TCSR register, if phy-num=1
in the DTS (or phy_number is set in the platform data).  The
SOC has 2 PHYs which can be used with the OTG port, and this
code allows configuring the correct one.

Note: This resolves the problem I was seeing where I couldn't
get the USB driver working at all on a dragonboard, from cold
boot.  This patch depends on patch 5/14 from Ivan's msm USB
patch set.  It does not use DT for the register address, as
there's no evidence that this address changes between SoC
versions.

Signed-off-by: Tim Bird <tim.bird@sonymobile.com>
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>