VFS: Minor fixes for porting.rst

This paragraph was relevant for an earlier version of the code which
passed the qstr as a struct instead of a point.  The version that landed
passed the pointer in all cases so this para is now pointless.

Signed-off-by: NeilBrown <neil@brown.name>
Link: https://lore.kernel.org/20250608230952.20539-3-neil@brown.name
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: neilbrown

Documentation/filesystems/porting.rst

@@ -1224,9 +1224,6 @@ lookup_noperm_unlocked(), lookup_noperm_positive_unlocked().  They now
 take a qstr instead of separate name and length.  QSTR() can be used
 when strlen() is needed for the length.
 
-For try_lookup_noperm() a reference to the qstr is passed in case the
-hash might subsequently be needed.
-
 These function no longer do any permission checking - they previously
 checked that the caller has 'X' permission on the parent.  They must
 ONLY be used internally by a filesystem on itself when it knows that