serial: UniPhier: add static to locally used functions

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>

drivers/serial/serial_uniphier.c

@@ -55,7 +55,7 @@ struct uniphier_serial_private_data {
 #define uniphier_serial_port(dev)	\
 	((struct uniphier_serial_private_data *)dev_get_priv(dev))->membase
 
-int uniphier_serial_setbrg(struct udevice *dev, int baudrate)
+static int uniphier_serial_setbrg(struct udevice *dev, int baudrate)
 {
 	struct uniphier_serial_platform_data *plat = dev_get_platdata(dev);
 	struct uniphier_serial __iomem *port = uniphier_serial_port(dev);
@@ -103,7 +103,7 @@ static int uniphier_serial_pending(struct udevice *dev, bool input)
 		return !(readb(&port->lsr) & UART_LSR_THRE);
 }
 
-int uniphier_serial_probe(struct udevice *dev)
+static int uniphier_serial_probe(struct udevice *dev)
 {
 	struct uniphier_serial_private_data *priv = dev_get_priv(dev);
 	struct uniphier_serial_platform_data *plat = dev_get_platdata(dev);
@@ -116,7 +116,7 @@ int uniphier_serial_probe(struct udevice *dev)
 	return 0;
 }
 
-int uniphier_serial_remove(struct udevice *dev)
+static int uniphier_serial_remove(struct udevice *dev)
 {
 	unmap_sysmem(uniphier_serial_port(dev));