serial: altera_uart: use BIT macro

Replace numerical bit shift with BIT macro
in altera_uart

:%s/(1 << nr)/BIT(nr)/g
where nr = 0, 1, 2 .... 31

Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Reviewed-by: Jagan Teki <jteki@openedev.com>
diff --git a/drivers/serial/altera_uart.c b/drivers/serial/altera_uart.c
index 4ff9fe2..7d5197a 100644
--- a/drivers/serial/altera_uart.c
+++ b/drivers/serial/altera_uart.c
@@ -27,9 +27,9 @@
 };
 
 /* status register */
-#define ALTERA_UART_TMT		(1 << 5)	/* tx empty */
-#define ALTERA_UART_TRDY	(1 << 6)	/* tx ready */
-#define ALTERA_UART_RRDY	(1 << 7)	/* rx ready */
+#define ALTERA_UART_TMT		BIT(5)	/* tx empty */
+#define ALTERA_UART_TRDY	BIT(6)	/* tx ready */
+#define ALTERA_UART_RRDY	BIT(7)	/* rx ready */
 
 DECLARE_GLOBAL_DATA_PTR;