iio: accel: kxcjk-1013: Fix kxcjk10013_set_range

Currently, we get the new GSEL bits by OR-ing the old values
with the new ones. This only works first time when the old
values are 0.

Startup:
* GSEL0 = 0, GSEL1 = 0

Set range to 4G: (GSEL0 = 1, GSEL1 = 0)
* GSEL0 = 0 | 1 = 1
* GSEL1 = 0 | 0 = 0
* correct

Change range to 2G: (GSEL0 = 0, GSEL1 = 0)
* GSEL0 = 1 | 0 = 1
* GSEL1 = 0 | 0 = 0
* wrong, GSEL0 should be 0

This has the nice effect that we can use the full scale range,
exported in in_accel_scale_available.

Fixes: a735e3d7f03 (iio: accel: kxcjk-1013: Set adjustable range)
Signed-off-by: Daniel Baluta <[e-mail]>
Reviewed-by: Srinivas Pandruvada <[e-mail]>
Cc: <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/accel/kxcjk-1013.c

···
 		return ret;
 	}
 
+	ret &= ~(KXCJK1013_REG_CTRL1_BIT_GSEL0 |
+		 KXCJK1013_REG_CTRL1_BIT_GSEL1);
 	ret |= (KXCJK1013_scale_table[range_index].gsel_0 << 3);
 	ret |= (KXCJK1013_scale_table[range_index].gsel_1 << 4);