ovl: remove unused forward declaration

JIRA: https://issues.redhat.com/browse/RHEL-83562

commit a6eb9a4
Author: Giuseppe Scrivano <gscrivan@redhat.com>
Date:   Mon Feb 10 13:07:55 2025 +0100

    ovl: remove unused forward declaration

    The ovl_get_verity_xattr() function was never added, only its declaration.

    Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
    Fixes: 184996e ("ovl: Validate verity xattr when resolving lowerdata")
    Reviewed-by: Amir Goldstein <amir73il@gmail.com>
    Reviewed-by: Alexander Larsson <alexl@redhat.com>
    Reviewed-by: Christian Brauner <brauner@kernel.org>
    Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>

Author: Miklos Szeredi

fs/overlayfs/overlayfs.h

@@ -529,8 +529,6 @@ int ovl_set_metacopy_xattr(struct ovl_fs *ofs, struct dentry *d,
 bool ovl_is_metacopy_dentry(struct dentry *dentry);
 char *ovl_get_redirect_xattr(struct ovl_fs *ofs, const struct path *path, int padding);
 int ovl_ensure_verity_loaded(struct path *path);
-int ovl_get_verity_xattr(struct ovl_fs *ofs, const struct path *path,
-			 u8 *digest_buf, int *buf_length);
 int ovl_validate_verity(struct ovl_fs *ofs,
 			struct path *metapath,
 			struct path *datapath);