config-gerrit: update repo download config options

This was renamed to just "repo" a while ago but the docs were missed.

Change-Id: I1dea13213e0c174c076a7ca47153abb406fa5db8

Documentation/config-gerrit.txt

diff --git a/Documentation/config-gerrit.txt b/Documentation/config-gerrit.txt
index c9b2a7f..e750450 100644
--- a/Documentation/config-gerrit.txt
+++ b/Documentation/config-gerrit.txt
@@ -1960,7 +1960,7 @@
   scheme = http
   scheme = anon_http
   scheme = anon_git
-  scheme = repo_download
+  scheme = repo
 ----
 
 The download section configures the allowed download methods.
@@ -2017,12 +2017,13 @@
 necessary to set <<gerrit.canonicalGitUrl,gerrit.canonicalGitUrl>>
 variable.
 +
-* `repo_download`
+* `repo`
 +
 Gerrit advertises patch set downloads with the `repo download`
 command, assuming that all projects managed by this instance are
-generally worked on with the repo multi-repository tool.  This is
-not default, as not all instances will deploy repo.
+generally worked on with the
+[repo multi-repository tool](https://gerrit.googlesource.com/git-repo).
+This is not default, as not all instances will deploy repo.
 
 +
 If `download.scheme` is not specified, SSH, HTTP and Anonymous HTTP