iio: adc: twl4030: Drop twl4030_get_madc_conversion()

Drop legacy twl4030_get_madc_conversion() method. It has been
used by drivers to get madc data before it conversion to IIO
API. There are no users in the mainline kernel anymore.
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.co.uk>
Acked-by: Wolfram Sang <wsa@the-dreams.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/twl4030-madc.c

@@ -642,27 +642,6 @@ int twl4030_madc_conversion(struct twl4030_madc_request *req)
 }
 EXPORT_SYMBOL_GPL(twl4030_madc_conversion);
 
-int twl4030_get_madc_conversion(int channel_no)
-{
-	struct twl4030_madc_request req;
-	int temp = 0;
-	int ret;
-
-	req.channels = (1 << channel_no);
-	req.method = TWL4030_MADC_SW2;
-	req.active = 0;
-	req.raw = 0;
-	req.func_cb = NULL;
-	ret = twl4030_madc_conversion(&req);
-	if (ret < 0)
-		return ret;
-	if (req.rbuf[channel_no] > 0)
-		temp = req.rbuf[channel_no];
-
-	return temp;
-}
-EXPORT_SYMBOL_GPL(twl4030_get_madc_conversion);
-
 /**
  * twl4030_madc_set_current_generator() - setup bias current
  *

include/linux/i2c/twl4030-madc.h

@@ -143,5 +143,4 @@ struct twl4030_madc_user_parms {
 };
 
 int twl4030_madc_conversion(struct twl4030_madc_request *conv);
-int twl4030_get_madc_conversion(int channel_no);
 #endif