If DISALLOW_USB_FILE_TRANSFER is set while the device is
connected via USB and data transfer is enabled, restart
the USB stack to make sure that data cannot be transferred any more
Fix: 34487750
Bug: 34054991
Test: Checked that files cannot be transferred any more as soon as the user restriction is set
Test: cts-tradefed run cts-dev --module DevicePolicyManager --test com.android.cts.devicepolicy.UserRestrictionsTest
Change-Id: I129c226e57da2d0be356f93436b36b3303cb604c