ffmpeg: remove incorrect network deinit

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit e2877bdf)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

ffmpeg.c

@@ -353,7 +353,6 @@ void term_init(void)
         signal(SIGQUIT, sigterm_handler); /* Quit (POSIX).  */
     }
 #endif
-    avformat_network_deinit();
 
     signal(SIGINT , sigterm_handler); /* Interrupt (ANSI).    */
     signal(SIGTERM, sigterm_handler); /* Termination (ANSI).  */