ARM: dts: msm: Add DRD mode for 2nd USB on MSM8996 Auto

Enable DRD mode for 2nd USB. Since, power supply class
is not used for it, user can change mode using sysfs
attribute. Commands:
 echo peripheral > /sys/devices/soc/7600000.hsusb/mode (Device)
 echo host > /sys/devices/soc/7600000.hsusb/mode (Host)
 echo none > /sys/devices/soc/7600000.hsusb/mode (Disconnect)

Change-Id: I9d859fa785d6ffd8bfbfa801399b48d698a19d5f
Signed-off-by: Manu Gautam <mgautam@codeaurora.org>