ubx: disable sbas configuration per default

src/drivers/gps/ubx.cpp

@@ -189,6 +189,7 @@ UBX::configure(unsigned &baudrate)
 		return 1;
 	}
 
+#ifdef UBX_CONFIGURE_SBAS
 	/* send a SBAS message to set the SBAS options */
 	memset(&_buf.payload_tx_cfg_sbas, 0, sizeof(_buf.payload_tx_cfg_sbas));
 	_buf.payload_tx_cfg_sbas.mode		= UBX_TX_CFG_SBAS_MODE;
@@ -198,6 +199,7 @@ UBX::configure(unsigned &baudrate)
 	if (wait_for_ack(UBX_MSG_CFG_SBAS, UBX_CONFIG_TIMEOUT, true) < 0) {
 		return 1;
 	}
+#endif
 
 	/* configure message rates */
 	/* the last argument is divisor for measurement rate (set by CFG RATE), i.e. 1 means 5Hz */