Far be it for me to defend religious rites :) - but a university is not just about a bunch of classrooms and laboratories. It is a community, with leisure facilities, restaurants, theatres even. And universities are open to all - and there will be many who have a strong religious conviction and wish to avail themselves of a place to pray.
Hence a prayer room.
As to this particular issue - I think I read somewhere that there was a high profile instance a few years ago where the occasion and venue was used to promote violence and anti-western sentiment, so one can understand the university authorities being anxious to get sight of the proposed sermons.
It is a form of censorship, I guess, and what you feel about this will be dependent upon how important you feel the issues of free speech and censorship. For myself, I think it is a form of censorship, and should not be tolerated. What the authorities should do, if they suspect this kind of radicalism, is get someone to attend and take notes, then come to a decision if they have evidence of anything that could be considered hate speech or incitement to violence....