isofs: Annotate struct SL_component with __counted_by()

Add the __counted_by compiler attribute to the flexible array member
text to improve access bounds-checking via CONFIG_UBSAN_BOUNDS and
CONFIG_FORTIFY_SOURCE.
Signed-off-by: Thorsten Blum <thorsten.blum@toblux.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240830164902.112682-2-thorsten.blum@toblux.com

fs/isofs/rock.h

@@ -44,7 +44,7 @@ struct RR_PN_s {
 struct SL_component {
 	__u8 flags;
 	__u8 len;
-	__u8 text[];
+	__u8 text[] __counted_by(len);
 } __attribute__ ((packed));
 
 struct RR_SL_s {