Added the step to fetch the submodules. Changed wording of the final steps slightly.

Compilation-guide-(Android-from-Linux).md

@@ -25,13 +25,22 @@ You can omit NOCLEAN=1 if you'd like to perform `make clean` on every core's rep
 
 ## Building RetroArch
 The RetroArch repo is fetched into the `libretro-super` folder as `retroarch` by `./libretro-fetch.sh` above.
+
+You first need to fetch the submodules for it.
 ```bash
-cd retroarch/pkg/android/phoenix
+cd retroarch
+git submodule update --init
+```
+Then set up the android projects.
+```bash
+cd pkg/android/phoenix
 android update project --path .
 android update project --path libs/googleplay/
 android update project --path libs/appcompat/ # this doesn't seem to exist anymore
 ```
 Now edit `local.properties` to point to the location of your ndk directory by adding a line like this: `ndk.dir=/complete/path/to/android-ndk-r9d`
+
+Finally, copy the cores, assets and overlays to the right place and build it.
 ```bash
 mkdir -p assets/cores
 mkdir assets/overlays