mfd: cs42l43: Use __u8 type rather than u8 for firmware interface

__xxx is the preferred type for firmware interfaces.
Suggested-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Link: https://lore.kernel.org/r/20240129152557.3221212-3-ckeepax@opensource.cirrus.comSigned-off-by: Lee Jones <lee@kernel.org>

drivers/mfd/cs42l43.c

@@ -55,8 +55,8 @@
 struct cs42l43_patch_header {
 	__le16 version;
 	__le16 size;
-	u8 reserved;
-	u8 secure;
+	__u8 reserved;
+	__u8 secure;
 	__le16 bss_size;
 	__le32 apply_addr;
 	__le32 checksum;