Merge branch 'so/diff-doc-for-patch-update'

References from description of the `--patch` option in various
manual pages have been simplified and improved.

* so/diff-doc-for-patch-update:
  doc/diff-options: fix link to generating patch section

Documentation/diff-options.txt

@@ -22,13 +22,7 @@ ifndef::git-format-patch[]
 -p::
 -u::
 --patch::
-	Generate patch (see section titled
+	Generate patch (see <<generate_patch_text_with_p>>).
-ifdef::git-log[]
-<<generate_patch_text_with_p, "Generating patch text with -p">>).
-endif::git-log[]
-ifndef::git-log[]
-"Generating patch text with -p").
-endif::git-log[]
 ifdef::git-diff[]
 	This is the default.
 endif::git-diff[]