Introduce Radio Shutdown System APIs for Mainline

Test: built; cts
Bug: 145554073
Change-Id: I26f01ea5f7cca88d1c3aeefae96ff3bf11b5138f
Merged-In: I26f01ea5f7cca88d1c3aeefae96ff3bf11b5138f
(cherry picked from commit 29131643f314a744b064b170f73f0e92ea59b693)
3 files changed