qcom-common: Update USB startup script

 * Needed to handle rmnet_usb startup on newer kernels

Change-Id: Id8a58b17af4fb5be506532030a28a26af2d277e1
qcom-common: Add RIL startup script for IPv6 tethering

Change-Id: I6c1fba6ea51451b218c5daae30ae0dc37838f7e0