regmap: missing case statement

This new code is unreachable.  Presumably there was supposed to be a
case statement there similar to the earlier code.

Fixes: afcc00b91f ('regmap: add 64-bit mode support')
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

drivers/base/regmap/regmap.c

@@ -844,6 +844,7 @@ struct regmap *__regmap_init(struct device *dev,
 		}
 		break;
 #ifdef CONFIG_64BIT
+	case 64:
 		switch (val_endian) {
 		case REGMAP_ENDIAN_BIG:
 			map->format.format_val = regmap_format_64_be;