Framerate cmdline argument fix

Changing used ffmpeg command line option from '-r' to '-framerate'

Author: mxpawl

plugins/hevc_enc/ffmpeg/src/hevc_enc_ffmpeg.cpp

@@ -120,7 +120,7 @@ ffmpeg_init
     }
 
     // frame rate
-    ffmpeg_call += " -r " + state->data->frame_rate;
+    ffmpeg_call += " -framerate " + state->data->frame_rate;
 
     // INPUT
     ffmpeg_call += " -i ";