[1/3] vim: move to system_ext

Change-Id: I71b228489cf0fd37242e2fc59e41171b30e83521
diff --git a/vimrc.android b/vimrc.android
index 2f74488..9589475 100644
--- a/vimrc.android
+++ b/vimrc.android
@@ -102,7 +102,7 @@
 endif
 
 if has("syntax")
-  source /system/usr/share/vim/autoload/spacehi.vim
+  source /system_ext/usr/share/vim/autoload/spacehi.vim
 endif
 
 " Convenient command to see the difference between the current buffer and the