A reference to some of the behaviors in the movie Superbad?

Protect yourself because they’re coming for you and the set you repping. “Splitting your onion” is slang for blowing someone’s brains out. Note the wordplay using the song name “Protect ya Neck” by Wu-Tang Clan. .

There is a slight play on words in this line and the next line. You chop onions when cooking. you cut, or split, a deck when playing cards. He switches these words to repeat the same metaphor for blowing someone’s brains out (split your onion then chop your deck).

In continuation with the subject matter of the previous line where he implies that he can fly (hence his use of the word, “wings”):
When you eat chicken wings that taste great you find yourself sucking the sauce off of the bones.

Weezy’s saying you can suck the sauce off Lil' Wayne’s “bone”.