Get entitlement configuration from intent extra

Tethering resource configuration is move from framwork to tethering
module. The resource would not be accessible from outside of tethering
module.
List the replacements of framework resources usage and intent extra:
1. R.string.config_mobile_hotspot_provision_response
    --> android.net.extra.TETHER_PROVISIONING_RESPONSE.
2. R.string.config_mobile_hotspot_provision_app_no_ui
    --> android.net.extra.TETHER_UI_PROVISIONING_APP_NAME
3. R.array.config_mobile_hotspot_provision_app
    --> android.net.extra.TETHER_SILENT_PROVISIONING_ACTION
Besides, the current active subId would put in
android.net.extra.TETHER_SUBID

Note: They are not APIs because of API freeze. Now both tethering module
and Settings define these strings independently. Will replace hard code
string as tethering module-lib APIs in b/159085857.

Also move the entitlement response intent registeration from onCreated
to onStartCommand, this can avoid wrong intent registeration if subId
changed between onCreate and when the intent arrived.

Bug: 146918263
Test: atest TetherServiceTest
      atest TetherProvisioningActivityTest

Change-Id: I3d06df01302a9c1f0893712d9250fe394dc66588
Merged-In: I3d06df01302a9c1f0893712d9250fe394dc66588