ffserver: do not ignore ff_socket_nonblock return

Should fix FFmpeg Coverity Scan issues #732180 & #732182

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
ffserver: do not ignore setsockopt return

Should fix FFmpeg Coverity Scan issue #732181

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
ffserver: do not ignore send() return

Should fix Coverity Scan issue #732178

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
ffserver: do not ignore getsockname() return

Should fix FFmpeg Coverity Scan issue #732176

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
ffserver: do not ignore lseek() return

Should fix FFmpeg Coverity Scan issue #732177

Signed-off-by: Reynaldo H. Verdejo Pinochet <r.verdejo@sisa.samsung.com>
avcodec/mpegvideo: fix null pointer dereference

Fixes: 111342.ogm with ffplay
Found-by: Dale Curtis <dalecurtis@google.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>