config/diff.txt: drop spurious backtick

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/config/diff.txt b/Documentation/config/diff.txt
index e48bb98..7a1bae1 100644
--- a/Documentation/config/diff.txt
+++ b/Documentation/config/diff.txt
@@ -10,7 +10,7 @@
 
 diff.dirstat::
 	A comma separated list of `--dirstat` parameters specifying the
-	default behavior of the `--dirstat` option to linkgit:git-diff[1]`
+	default behavior of the `--dirstat` option to linkgit:git-diff[1]
 	and friends. The defaults can be overridden on the command line
 	(using `--dirstat=<param1,param2,...>`). The fallback defaults
 	(when not changed by `diff.dirstat`) are `changes,noncumulative,3`.