Add RIL_REQUEST_SHUTDOWN to notify RIL that device is shutting down

When device is in airplane mode, SIM card and modem may be powered on.
RIL can use RIL_REQUEST_SHUTDOWN to shutdown the modem and SIM card

Bug: 9773278
Change-Id: I6afa9e810cefc7855f7ae42e51f39cc51fa2aa6e
4 files changed
tree: 2193567b4291928f6bf16db47487414ac9c64f56
  1. include/
  2. libril/
  3. librilutils/
  4. reference-ril/
  5. rild/