iio: magnetometer: mmc35240: Fix sensitivity on z-axis

Datasheet says (Page 2) that typical value for sensitivity
for 16 bits mode on Z-axis is 770. Anyhow, looking at the
input driver provided by Memsic the value for MMC35240 is
1024.

Also, testing shows that using 1024 for Z-axis senzitivity
offers better results.

Fixes: abeb6b1e7b ("iio: magnetometer: Add support for MEMSIC MMC35240")
Signed-off-by: Daniel Baluta <daniel.baluta@intel.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/magnetometer/mmc35240.c

@@ -77,7 +77,7 @@ static const struct {
 } mmc35240_props_table[] = {
 	/* 16 bits, 100Hz ODR */
 	{
-		{1024, 1024, 770},
+		{1024, 1024, 1024},
 		32768,
 	},
 	/* 16 bits, 200Hz ODR */