Hyphenated here because the phrase has been made into a verb!

• 01.016 to be good-morninged by Belladonna Took’s son,

A perfectly robust OED entry, with instances beginning in 1802, and continuing through some very recent great literature:

1988   D. Adams Long Dark Tea-time of Soul (1991) vii. 76   The orderly arrived promptly in his well-pressed loose green tunic, good-morninged cheerfully, and bustled around locating bedroom slippers and dressing gown.

I should note that this line of the Hobbit is one of the OED examples of this word.

“good-morning, v.” OED Online, Oxford University Press, June 2017, http://www.oed.com/view/Entry/321166. Accessed 13 September 2017.