Ah, *that's* where that readme is.
I'd looked all over the www mirrors for that readme.
(Hows about having a pointer on the mirrors that points me to my hard drive as in "hey dummy the mkinitrd readme is not here, it's located on your hard drive in the /boot folder".)
I did like the 2nd mkinitrd example in that readme.
And, the error is gone. Works fine.
I had booted it several times with the error. So, I wonder if there is anything else that I need to do? Such as run fsck? (and/or) run what command?