Comment 8 for bug 1548120

Ok, it seems that busybox tr does not actually support symbolic ranges. Rather than add a first user of awk it seems simpler to manually expand the character ranges. Specifically as the specification says the following:

    "The hexadecimal values "a" through "f" are output as lower case characters and are case insensitive on input."

we can simply map A-F to a-f and cover all valid cases.

@manjo -- I have uploaded this fix to my ppa:apw/ubuntu/initramfs-tools-test for testing. Could you do one final test with that one before I break the archive again.