Rename system_radio_prop

For whatever reason sys.usb.config* has been labeled as
system_radio_prop, which doesn't make sense. Changing context name as
usb_prop. For the same reason exported_system_radio_prop is also
renamed to usb-related names.

Bug: 71814576
Bug: 154885206
Test: m selinux_policy
Change-Id: If30bc620dbeac926a8b9bcde908357fda739a6c1
Merged-In: If30bc620dbeac926a8b9bcde908357fda739a6c1
(cherry picked from commit 44fbcdb677d040a7ff9949db8457347a5299b4a0)
12 files changed