usb: Initialize restricted radio button for USB settings

Initialize the selector widget on RadioButtonPickerFragment.java as a
restricted selector to avoid the crash in the attached bug.

Recording - admin managed settings: https://drive.google.com/file/d/1PHBbgAqcMMUT1oOBMydNhCAByXZtrHQ4/view?usp=sharing&resourcekey=0-BMCFViZej4UAls309ijsFA
Recording: https://drive.google.com/file/d/1J-9rphVDPByn-LTlRb2WfByd-TZr8Tel/view?usp=drive_link&resourcekey=0-aXkIhmL6V8pMvvo_5K8l0A

Bug: 416640194
Test: Manual. See recordings for evidence.
Flag: EXEMPT bugfix

Change-Id: I48a74a4337a43d1c3b0ba85d4f8f4998800820fe