Update documentation to use --recurse-submodules instead of --recursive

The --recursive option is an alias of --recurse-submodules, and
git's autocompletion will select --recurse-submodules rather than
--recursive.

Change-Id: I5aab184cbcdeffb14bf3e82363936299daddde27
diff --git a/README.md b/README.md
index 844ee48..a9582b0 100644
--- a/README.md
+++ b/README.md
@@ -52,7 +52,7 @@
 
 Install [Bazel](https://bazel.build/versions/master/docs/install.html) and run the following:
 
-        git clone --recursive https://gerrit.googlesource.com/gerrit
+        git clone --recurse-submodules https://gerrit.googlesource.com/gerrit
         cd gerrit && bazel build release
 
 ## Install binary packages (Deb/Rpm)