Gyro controls

[IceBaronTwinAcc]

Hello, developers of Source for Android. I've been using your port on my phone and I must say the game runs and plays well. However, I recently played Portal 1 and 2 on my Nintendo Switch using the Companion Cube Collection, and that port features aiming using the gyroscopes in the controllers, which made aiming with a controller much easier without using aim assist or such. So, I ask you to add gyto controls to this port as well, as aiming with a touchscreen is also tricky.