staging: comedi: me4000: tidy up ME4000_AO_STATUS_REG bit defines

Use the BIT() marco to define the bits of this register.

For aesthetics, rename all the defines to remove the '_BIT' from the
name.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reviewed-by: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/me4000.c

@@ -69,10 +69,10 @@ broken.
 #define ME4000_AO_CTRL_BIT_ENABLE_IRQ		(1 << 9)
 #define ME4000_AO_CTRL_BIT_RESET_IRQ		(1 << 10)
 #define ME4000_AO_STATUS_REG(x)			(0x04 + ME4000_AO_CHAN(x))
-#define ME4000_AO_STATUS_BIT_FSM		(1 << 0)
-#define ME4000_AO_STATUS_BIT_FF			(1 << 1)
-#define ME4000_AO_STATUS_BIT_HF			(1 << 2)
-#define ME4000_AO_STATUS_BIT_EF			(1 << 3)
+#define ME4000_AO_STATUS_FSM			BIT(0)
+#define ME4000_AO_STATUS_FF			BIT(1)
+#define ME4000_AO_STATUS_HF			BIT(2)
+#define ME4000_AO_STATUS_EF			BIT(3)
 #define ME4000_AO_FIFO_REG(x)			(0x08 + ME4000_AO_CHAN(x))
 #define ME4000_AO_SINGLE_REG(x)			(0x0c + ME4000_AO_CHAN(x))
 #define ME4000_AO_TIMER_REG(x)			(0x10 + ME4000_AO_CHAN(x))