iio: magnetometer: ak8975: Fix 'Unexpected device' error

Explicity specify array indices to fix mapping between
asahi_compass_chipset and ak_def_array.
While at it, remove unneeded AKXXXX.

Fixes: 4f9ea93a ("iio: magnetometer: ak8975: Convert enum->pointer for data in the match tables")
Signed-off-by: André Apitzsch <git@apitzsch.eu>
Reviewed-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20231001-ak_magnetometer-v1-1-09bf3b8798a3@apitzsch.euSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/magnetometer/ak8975.c

@@ -204,7 +204,6 @@ static long ak09912_raw_to_gauss(u16 data)
 
 /* Compatible Asahi Kasei Compass parts */
 enum asahi_compass_chipset {
-	AKXXXX		= 0,
 	AK8975,
 	AK8963,
 	AK09911,
@@ -248,7 +247,7 @@ struct ak_def {
 };
 
 static const struct ak_def ak_def_array[] = {
-	{
+	[AK8975] = {
 		.type = AK8975,
 		.raw_to_gauss = ak8975_raw_to_gauss,
 		.range = 4096,
@@ -273,7 +272,7 @@ static const struct ak_def ak_def_array[] = {
 			AK8975_REG_HYL,
 			AK8975_REG_HZL},
 	},
-	{
+	[AK8963] = {
 		.type = AK8963,
 		.raw_to_gauss = ak8963_09911_raw_to_gauss,
 		.range = 8190,
@@ -298,7 +297,7 @@ static const struct ak_def ak_def_array[] = {
 			AK8975_REG_HYL,
 			AK8975_REG_HZL},
 	},
-	{
+	[AK09911] = {
 		.type = AK09911,
 		.raw_to_gauss = ak8963_09911_raw_to_gauss,
 		.range = 8192,
@@ -323,7 +322,7 @@ static const struct ak_def ak_def_array[] = {
 			AK09912_REG_HYL,
 			AK09912_REG_HZL},
 	},
-	{
+	[AK09912] = {
 		.type = AK09912,
 		.raw_to_gauss = ak09912_raw_to_gauss,
 		.range = 32752,
@@ -348,7 +347,7 @@ static const struct ak_def ak_def_array[] = {
 			AK09912_REG_HYL,
 			AK09912_REG_HZL},
 	},
-	{
+	[AK09916] = {
 		.type = AK09916,
 		.raw_to_gauss = ak09912_raw_to_gauss,
 		.range = 32752,