staging:iio:adc remove unused adc.h.

Another header unused after chan_spec conversions.
Signed-off-by: NJonathan Cameron <jic23@cam.ac.uk>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>

drivers/staging/iio/adc/adc.h

-/*
- * adc.h - sysfs attributes associated with ADCs
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License version 2 as published by
- * the Free Software Foundation.
- *
- * Copyright (c) 2008 Jonathan Cameron <jic23@cam.ac.uk>
- *
- */
-
-/* Deprecated */
-#define IIO_DEV_ATTR_ADC(_num, _show, _addr)			\
-  IIO_DEVICE_ATTR(adc_##_num, S_IRUGO, _show, NULL, _addr)
-
-#define IIO_DEV_ATTR_IN_RAW(_num, _show, _addr)				\
-	IIO_DEVICE_ATTR(in##_num##_raw, S_IRUGO, _show, NULL, _addr)
-
-#define IIO_DEV_ATTR_IN_NAMED_RAW(_num, _name, _show, _addr)		\
-	IIO_DEVICE_ATTR(in##_num##_##_name##_raw, S_IRUGO, _show, NULL, _addr)
-
-#define IIO_DEV_ATTR_IN_DIFF_RAW(_nump, _numn, _show, _addr)		\
-	IIO_DEVICE_ATTR_NAMED(in##_nump##min##_numn##_raw,		\
-			      in##_nump-in##_numn##_raw,		\
-			      S_IRUGO,					\
-			      _show,					\
-			      NULL,					\
-			      _addr)
-
-
-#define IIO_CONST_ATTR_IN_NAMED_OFFSET(_num, _name, _string)	\
-	IIO_CONST_ATTR(in##_num##_##_name##_offset, _string)
-
-#define IIO_CONST_ATTR_IN_NAMED_SCALE(_num, _name, _string)	\
-	IIO_CONST_ATTR(in##_num##_##_name##_scale, _string)
-
-#define IIO_EVENT_CODE_IN_HIGH_THRESH(a)				\
-	IIO_UNMOD_EVENT_CODE(IIO_EV_CLASS_IN, a, IIO_EV_TYPE_THRESH,	\
-			     IIO_EV_DIR_RISING)
-#define IIO_EVENT_CODE_IN_LOW_THRESH(a)				     \
-	IIO_UNMOD_EVENT_CODE(IIO_EV_CLASS_IN, a, IIO_EV_TYPE_THRESH, \
-			     IIO_EV_DIR_FALLING)