prepare cellbroadcastreceiver to be a mainline module

1. prepare two build targets one for updatable module another
for the legacy platform module with diferent config
2. a new cellbroadcastpermissionconfig module to expose
a signature permission.
3. by default, the build include the legacy version.
Later we will switch to the updatable module after more validation
e.g, usre data migration due to uid change
4. for go devies, always include the platform cellbroadcast to
to avoid creating new process

Bug: 135956699
Test: unit test and test app

Change-Id: I4d757e27b1e36fbf4890d08afbd45a141bccfc7c