merge: update documentation for {merge,diff}.renameLimit

Update the documentation to better indicate that the renameLimit setting is
ignored if rename detection is turned off via command line options or config
settings.

Signed-off-by: Ben Peart <benpeart@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/diff-config.txt

@@ -112,7 +112,8 @@ diff.orderFile::
 
 diff.renameLimit::
 	The number of files to consider when performing the copy/rename
-	detection; equivalent to the 'git diff' option `-l`.
+	detection; equivalent to the 'git diff' option `-l`. This setting
+	has no effect if rename detection is turned off.
 
 diff.renames::
 	Whether and how Git detects renames.  If set to "false",

Documentation/merge-config.txt

@@ -35,7 +35,8 @@ include::fmt-merge-msg-config.txt[]
 merge.renameLimit::
 	The number of files to consider when performing rename detection
 	during a merge; if not specified, defaults to the value of
-	diff.renameLimit.
+	diff.renameLimit. This setting has no effect if rename detection
+	is turned off.
 
 merge.renormalize::
 	Tell Git that canonical representation of files in the