A verse from the Irish ditty "Leaving Tipperary" (aka "Goodbye Mick"):
In my portmanteau I have some cabbage, beans and bacon
and if you think I can't eat that, well there's where you're mistaken
For if the ship will pitch and toss, for half a dozen farthings
I'll take me bundle on me back and walk to Castle Gardens.
There's also a Bluegrass version with different words.
“portmanteau” is a weird word with completely unrelated meanings. In that ditty you quoted, it is a synonym for “suitcase.”
In my quote, it means mashing two words together to create an entirely new word.