Highgui test output fixes.

Useless output to console fixed;
Test output files moved from cwd to temp folder.
(cherry picked from commit 87935f35)

modules/highgui/test/test_ffmpeg.cpp

@@ -88,7 +88,7 @@ public:
             stringstream s;
             s << tag;
 
-            const string filename = "output_"+s.str()+".avi";
+            const string filename = tempfile((s.str()+".avi").c_str());
 
             try
             {

modules/highgui/test/test_video_io.cpp

@@ -332,9 +332,7 @@ void CV_HighGuiTest::VideoTest(const string& dir, const cvtest::VideoFormat& fmt
         }
     }
 
-    printf("Before saved release for %s\n", tmp_name.c_str());
     cvReleaseCapture( &saved );
-    printf("After release\n");
 
     ts->printf(ts->LOG, "end test function : ImagesVideo \n");
 }