initramfs: dont install 'diskdev_cmds' in initramfs

Signed-off-by: Stephan Raue <stephan@openelec.tv>
diskdev_cmds: dont build 'diskdev_cmds:init' target

Signed-off-by: Stephan Raue <stephan@openelec.tv>
tools/mkpkg: remove mkpkg_crystalhd* scripts

Signed-off-by: Stephan Raue <stephan@openelec.tv>