usb: chipidea: msm: Use USB PHY API to control PHY state

PHY drivers keep track of the current state of the hardware,
so don't change PHY settings under it.

Cc: 3.16+ <stable@vger.kernel.org>
Cc: Tim Bird <tbird20d@gmail.com>
Signed-off-by: Peter Chen <peter.chen@freescale.com>
Signed-off-by: Ivan T. Ivanov <iivanov@mm-sol.com>
Acked-by: Felipe Balbi <balbi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>