tty: serial: bcm63xx_uart: define UART_REG_SIZE constant

The bcm63xx_uart driver uses RSET_UART_SIZE which is a constant defined
for MIPS-based BCM63xx platforms, pull this constant value from the
MIPS-specific header and put it in include/linux/serial_bcm63xx.h to
make the driver platform agnostic.

Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/include/linux/serial_bcm63xx.h b/include/linux/serial_bcm63xx.h
index 570e964..a80aa1a 100644
--- a/include/linux/serial_bcm63xx.h
+++ b/include/linux/serial_bcm63xx.h
@@ -116,4 +116,6 @@
 					UART_FIFO_PARERR_MASK |		\
 					UART_FIFO_BRKDET_MASK)
 
+#define UART_REG_SIZE			24
+
 #endif /* _LINUX_SERIAL_BCM63XX_H */