Add config flag for enabling SIP/phone integration.

    <!-- Enables SIP on WIFI only -->

    <bool name="config_sip_wifi_only">true</bool>

    <!-- Enables built-in SIP phone capability -->

    <bool name="config_built_in_sip_phone">false</bool>

    <!-- Boolean indicating if restoring network selection should be skipped -->

    <!-- The restoring is handled by modem if it is true-->

    <bool translatable="false" name="skip_restoring_network_selection">false</bool>