- cleanup the evaluation of kiwi_ variables inside the initrd
  + the following elements/attributes accepts true|false values:
    <oem-kiwi-initrd>, compressed, hybrid, hybridpersistent and ramonly
    These settings are propagated without changes to the linuxrc code
    that evaluates the variable to decide whether or not to perform
    an action. The evaluation in the shell code was based on yes|no
    an old relic that used to be use in the XML a long time ago.
    This update changes the evaluation in the shell code
    to true|false.