FPS to Hertz in a camera
The physical definition of frequency is the number of oscillations per second and measured in Hertz (Hz) or more general: 1/(duration of one period of a periodic event in seconds). In your case the periodic event is a frame and it occurs 120 times per second so the frequency is 120 Hz.

If you want to find out the sampling frequency of the ADC device in the camera you could calculate it like that:
$$
f_\mathrm{s} = N_\mathrm{pixel} \cdot R_\mathrm{frame}
$$
where $N_\mathrm{pixel}$ is the number of pixels in the sensor and $R_\mathrm{frame}$ is the frame rate. With the numbers from the data sheet I obtain a sampling frequency of 12.3 MHz. I can't tell if this is the actual frequency used by the camera. If it uses oversampling or interlacing the value could differ.