SERIAL: omap: remove 'irq_pending' bitfield

irq_pending is never used, so let's remove it.  It seems to be  result
of a bad rebase of d37c6cebcb0c (serial: omap: move uart_omap_port
definition to C file)

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/drivers/tty/serial/omap-serial.c b/drivers/tty/serial/omap-serial.c
index 170be2b..da46be3 100644
--- a/drivers/tty/serial/omap-serial.c
+++ b/drivers/tty/serial/omap-serial.c
@@ -99,7 +99,6 @@
 	u32			context_loss_cnt;
 	u32			errata;
 	u8			wakeups_enabled;
-	unsigned int		irq_pending:1;
 
 	int			DTR_gpio;
 	int			DTR_inverted;