ARM: dts: msm: Add a gpio for extcon_usb1 node

Everytime device switch to usb host mode, trigger
this gpio to reset ethernet bridge (LAN78xx) and
ethernet usb driver can be probed.

Change-Id: I2e0fa48cb72eb89b8a88e55526851ea95c5c696d
Signed-off-by: Bo Zhang <bozhang@codeaurora.org>