debugfs: drop inline constant formatting for ERR_PTR(-ERROR)

Stephen Rothwell reported htmldocs warning when merging driver-core tree
for linux-next:

Documentation/filesystems/api-summary:146: fs/debugfs/inode.c:804: WARNING: Inline literal start-string without end-string.

The warning is due to inline constant formatting (``%CONST``) doesn't play
nice with complex-name constants like ERR_PTR(-ERROR).

Drop the formatting for that constant above to be consistent with similar
error constants and also to fix the above warning.

Link: https://lore.kernel.org/lkml/20230220163133.481e43d8@canb.auug.org.au/
Fixes: d300246 ("debugfs: update comment of debugfs_rename()")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Link: https://lore.kernel.org/r/20230220124721.11657-1-bagasdotme@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: bagasme

fs/debugfs/inode.c

@@ -802,7 +802,7 @@ EXPORT_SYMBOL_GPL(debugfs_lookup_and_remove);
  * exist for rename to succeed.
  *
  * This function will return a pointer to old_dentry (which is updated to
- * reflect renaming) if it succeeds. If an error occurs, %ERR_PTR(-ERROR)
+ * reflect renaming) if it succeeds. If an error occurs, ERR_PTR(-ERROR)
  * will be returned.
  *
  * If debugfs is not enabled in the kernel, the value -%ENODEV will be