Revert "root: msm8960 needs mtp,usbnet,adb"

This reverts commit b2aca983138f53a0083d47746214c8a9ea522ed3.
This was needed when old usb PIDs were used, to match Motorola usb
drivers for Windows. Now, when new PIDs are used, usbnet must go
away, so interface numbers (MI) match again.
This resolves adb driver installation issues reported by Windows
users.

Change-Id: I84f0424c62d4bf72a7cb2f514c1617b116dd6933