img2dec: Support Progressive JPEG in jpeg_probe

There can be multiple SOS markers, so do not return 0 in that case.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

libavformat/img2dec.c

@@ -714,7 +714,7 @@ static int jpeg_probe(AVProbeData *p)
             state = 0xC0;
             break;
         case 0xDA:
-            if (state != 0xC0)
+            if (state != 0xC0 && state != 0xDA)
                 return 0;
             state = 0xDA;
             break;