fix(video): base min frame time strictly on client framerate (#3844)

src/config.h

@@ -140,7 +140,6 @@ namespace config {
       workarounds_t wa;
     } dd;
 
-    int min_fps_factor;  // Minimum fps target, determines minimum frame time
     int max_bitrate;  // Maximum bitrate, sets ceiling in kbps for bitrate requested from client
   };