Description of problem:
RHEL-8 is currently missing support for option like,
Version-Release number of selected component (if applicable):
Steps to Reproduce:
1. man systemd-cryptsetup-generator
Above form of the luks.key option is not described in man page and doesn't work
Option is described in the man page and block device can be unlocked using keydev.
fix merged to staging branch -> https://github.com/lnykryn/systemd-rhel/pull/251 -> post