port-probe: explicitly report GPS port type if port flagged

And remove all custom logic from all plugins that were doing just that.

plugins/mbm/mm-plugin-mbm.c

@@ -65,33 +65,6 @@ create_modem (MMPlugin *self,
                                                       product));
 }
 
-static gboolean
-grab_port (MMPlugin *self,
-           MMBaseModem *modem,
-           MMPortProbe *probe,
-           GError **error)
-{
-    MMPortSerialAtFlag pflags = MM_PORT_SERIAL_AT_FLAG_NONE;
-    MMKernelDevice *port;
-    MMPortType port_type;
-
-    port_type = mm_port_probe_get_port_type (probe);
-    port = mm_port_probe_peek_port (probe);
-
-    if (mm_kernel_device_get_property_as_boolean (port, "ID_MM_PORT_TYPE_GPS")) {
-        mm_dbg ("(%s/%s) Port flagged as GPS",
-                mm_port_probe_get_port_subsys (probe),
-                mm_port_probe_get_port_name (probe));
-        port_type = MM_PORT_TYPE_GPS;
-    }
-
-    return mm_base_modem_grab_port (modem,
-                                    port,
-                                    port_type,
-                                    pflags,
-                                    error);
-}
-
 /*****************************************************************************/
 
 G_MODULE_EXPORT MMPlugin *
@@ -124,6 +97,4 @@ mm_plugin_mbm_class_init (MMPluginMbmClass *klass)
     MMPluginClass *plugin_class = MM_PLUGIN_CLASS (klass);
 
     plugin_class->create_modem = create_modem;
-    plugin_class->grab_port = grab_port;
-
 }