Use --recursive option for git clone

Linux-Build.md

@@ -33,11 +33,12 @@ If you're on Arch Linux, you can use `pacman -S glfw` instead.
 ### Cloning Citra in Git:
 
 ```
-git clone https://github.com/citra-emu/citra
+git clone --recursive https://github.com/citra-emu/citra
 cd citra
-git submodule update --init
 ```
 
+The `--recursive` option automatically clones the required Git submodules too.
+
 ### Building Citra:
 
 ```