Make /storage/emulated/0 exist for various things that give a crap about it

ps2: apply change in a way that will work on any kernel with working sysinit in their amateurish precompiled ramdisk... but I'm not bitter about them having precompiled ramdisks... oh, so not bitter.

Change-Id: I28cd93e777e73fe63a1d29800c8d91d0cb7a9f30