Can I control just a ceiling fan light kit with the switch and leave the fan powered?

As others have said you could add the extra wiring which should be fairly easy given the wiring is in conduit.

An alternate option would be to leave the wiring mostly as is and simply add a ceiling fan remote control. You can by one for $20-30. These come in two parts. The part that you insert in the ceiling fan that sits between the switch and the fan/light and the remote. The are sold as generic units that work with almost all ceiling fans/lights.

Even with conduit adding the remote is probably easier and meets the requirement of allowing you to individually control the fan and light.