staging: comedi: ni_at_ao: fix namespace clash of 'RSI' define

As pointed out by Fengguang Wu, the RSI define in this driver clashes
with the one in arch/x86/include/uapi/asm/ptrace-abi.h.

This define isn't currently used by the driver so just rename it to fix
the clash.
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Cc: Ian Abbott <abbotti@mev.co.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/comedi/drivers/ni_at_ao.c

@@ -110,7 +110,7 @@ Configuration options:
 #define BCD		0x01
 
 #define ATAO_2_RTSISHFT		0x06	/* W 8 */
-#define RSI		0x01
+#define ATAO_RTSISHFT_RSI	(1 << 0)
 
 #define ATAO_2_RTSISTRB		0x07	/* W 8 */