camera_frame_stream.h: remove unused variables (#20340)

selfdrive/camerad/cameras/camera_frame_stream.h

@@ -14,20 +14,16 @@
 #define FRAME_BUF_COUNT 16
 
 typedef struct CameraState {
-  int camera_id;
   int camera_num;
   CameraInfo ci;
 
   int fps;
   float digital_gain;
-  float cur_gain_frac;
 
   CameraBuf buf;
 } CameraState;
 
 typedef struct MultiCameraState {
-  int ispif_fd;
-
   CameraState road_cam;
   CameraState driver_cam;