defconfig: msm9625: Enable USB device

Enable HSUSB gadget drivers on msm9625.

Also enable USB_BAM. Even though the usb_bam device tree node
does not exist yet, its driver functions should safely return
error values when called, and will allow the usb bam2bam gadget
functions to enumerate.

Change-Id: I02e81d07df2f4582c7b58f32d9466a311620cb55
Signed-off-by: Jack Pham <jackp@codeaurora.org>