Who put the Ojibwe phrase on the board at Tony's hospital room?

It remains unknown.

"Who gives a s@%# about this Russian?” --David Chase

Not everything gets solved in The Sopranos. The most famous examples of this particular narrative tendency are the mystery of the vanishing Russian in Pine Barrens, and of course

the show's ambiguous ending.

Putting aside the significance of the quote itself and the role of wind in that cluster of season 6 episodes (though it's an interesting topic), how the Ojibwe saying got to Tony's room is just one of the show's unresolved mysteries. Tony suspects it's his sister in The Fleshy Part of the Thigh:

Nurse: Who put that up?

Tony: My sister. Who else?

Nurse: Why do you keep it up there if you don't find it inspirational?

Tony: My daughter likes it.

However, Janice denies this later in the episode:

Janice: What, you think I put that up there? I didn't.

Tony: Right. Then who did?

Now, I watched this series more than once and remember it pretty well and I'm quite sure Tony's question is never answered. It could be anyone and, in fact, it's easier to guess who didn't put it up:

• It's probably not the dreadlocked nurse or Chris because they wonder about it too;
• Janice denies it's her;
• From what Tony says, it's probably not Meadow either (he does say she liked it but still supposes it was Janice).

Throughout the series, Tony, who's supposed to be a no-nonsense tough-guy, finds himself unwillingly drawn to ponder the deeper mysteries of his own existence; it's what makes him so conflicted and compelling. So not knowing who put up the quote makes him wonder not only what the quote means but also what its actual origin is - and cleverly puts us in the same boat with him.