Ramdisk cleanup

* Adjust permissions to match stock ramdisk
* Move permissions into ueventd.xxx file
* Remove unnecesary configuration
* Move mknod into .fs.rc, and ensure that recovery uses it

Note: Bluetooth may need to be repaired after this change. It will
go into a new init.bcm21553.bt.rc configuration file.

Change-Id: I0fbc8dd6d3fbafc764885d5022edf27b2a882b31