ARM: dts: msm: Enable autosuspend for USB device for msm8937

Enable required dts property to enable autosuspend for USB
platform device for msm8937 to fix unnecessarily exit/enter
low power modes during host mode stop.

Change-Id: I0f7be6d22479626e1bec115d1a4e0e640bdc21fb
Signed-off-by: Vijayavardhan Vennapusa <vvreddy@codeaurora.org>