bsc: Add parameter to restart a bts

The ip.access nanoBTS seems to have severe issues with BSSGP when
changing the country code and/or network code. It is unlikely that
the proprietary code is getting fixed so we extend the parameter
for the apply-configuration command to carry the 'restart' param.

openbsc/src/libbsc/bsc_ctrl_commands.c

@@ -90,7 +90,17 @@ static int set_net_apply_config(struct ctrl_cmd *cmd, void *data)
 		if (!is_ipaccess_bts(bts))
 			continue;
 
-		ipaccess_drop_oml(bts);
+		/*
+		 * The ip.access nanoBTS seems to be unrelaible on BSSGP
+		 * so let's us just reboot it. For the sysmoBTS we can just
+		 * restart the process as all state is gone.
+		 */
+		if (!is_sysmobts_v2(bts) && strcmp(cmd->value, "restart") == 0) {
+			struct gsm_bts_trx *trx;
+			llist_for_each_entry_reverse(trx, &bts->trx_list, list)
+				abis_nm_ipaccess_restart(trx);
+		} else
+			ipaccess_drop_oml(bts);
 	}
 
 	cmd->reply = "Tried to drop the BTS";