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

Enable DRD mode for secondary USB controller of MSM8996 Auto
target. User can change the mode using sysfs.
Eg:
   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: Ia1d9c115b6fed01a7ab3a9f0489d6eb9d735a282
Signed-off-by: Ajay Agarwal <ajaya@codeaurora.org>