@intoparent, how would you feel if your daughter moved into her freshman dorm and found out that her roommate was a 6 foot tall 200 pound man? The OP’s roommate deserves to know she is moving in with a man.
If the OP was gay I would agree that it is no business of the roommate. That the OP is male is a whole different ballgame. I wouldn’t be uncomfortable with my daughter rooming with a mtf transgender but a ftm would make things far more awkward.
And being upfront ahead of time is also making it less awkward for the OP.