Use a better fix for 32bit x11 libraries on 11.10

Ubuntu package naming is apparently really inconsistent during
this time as they transition to using the package:arch syntax.

Change-Id: I3ce79de01b368b95f26c0d44473e07d6604ddbf7
diff --git a/src/source/initializing.md b/src/source/initializing.md
index 3660c16..e2d8a3d 100644
--- a/src/source/initializing.md
+++ b/src/source/initializing.md
@@ -83,7 +83,7 @@
 
 On Ubuntu 11.10:
 
-    $ sudo ln -s /usr/lib/i386-linux-gnu/libX11.so.6 /usr/lib/i386-linux-gnu/libX11.so
+    $ sudo apt-get install libx11-dev:i386
 
 32-bit (experimental)