tty: serial: owl-uart, send x_char even if stopped

Flow control characters should be sent even if the TX is stopped. So fix
owl-uart to behave the same as other drivers.

This unification also allows the use of the TX helper in the future.

Cc: "Andreas Färber" <afaerber@suse.de>
Cc: Manivannan Sadhasivam <mani@kernel.org>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20220411104506.8990-3-jslaby@suse.czSigned-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/tty/serial/owl-uart.c

@@ -184,9 +184,6 @@ static void owl_uart_send_chars(struct uart_port *port)
 	struct circ_buf *xmit = &port->state->xmit;
 	unsigned int ch;
 
-	if (uart_tx_stopped(port))
-		return;
-
 	if (port->x_char) {
 		while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU))
 			cpu_relax();
@@ -195,6 +192,9 @@ static void owl_uart_send_chars(struct uart_port *port)
 		port->x_char = 0;
 	}
 
+	if (uart_tx_stopped(port))
+		return;
+
 	while (!(owl_uart_read(port, OWL_UART_STAT) & OWL_UART_STAT_TFFU)) {
 		if (uart_circ_empty(xmit))
 			break;