lavfi/hue: extend debugging message

In particular, show h value in degrees.

libavfilter/vf_hue.c

@@ -270,11 +270,12 @@ static int filter_frame(AVFilterLink *inlink, AVFrame *inpic)
         hue->hue = hue->hue_deg * M_PI / 180;
     } else if (hue->hue_expr) {
         hue->hue = av_expr_eval(hue->hue_pexpr, hue->var_values, NULL);
+        hue->hue_deg = hue->hue * 180 / M_PI;
     }
 
     av_log(inlink->dst, AV_LOG_DEBUG,
-           "H:%0.1f s:%0.f t:%0.1f n:%d\n",
-           hue->hue, hue->saturation,
+           "H:%0.1f*PI h:%0.1f s:%0.f t:%0.1f n:%d\n",
+           hue->hue/M_PI, hue->hue_deg, hue->saturation,
            hue->var_values[VAR_T], (int)hue->var_values[VAR_N]);
 
     compute_sin_and_cos(hue);