For those that don't know what that is, here is the entirety of the text of that clause
No title of nobility shall be granted by the United States: and no person holding any office of profit or trust under them, shall, without the consent of the Congress, accept of any present, emolument, office, or title, of any kind whatever, from any king, prince, or foreign state.
Trump is NOT in violation of this clause. And it is a hillarious claim coming from anyone that voted for Hillary, who would have been actually in violation of this clause, with the Clinton Foundation.
Typically, all "Gifts" from foreign heads of state are property of the US Government and are placed in the public trust.
What this poster is trying to say, is that Trump cannot rent his hotel rooms out to people because that is a "gift".
Here is the definition:
a salary, fee, or profit from employment or office.
I wonder where all these people were when Hillary was SoS and Bill was being paid by all those rich Arab Princes and Kings for giving speeches. Why suddenly they are "horrified" that Trump owns a business that might rent a hotel room to a prince, but said nothing for 4 years while the Clinton's enriched themselves.