avcodec/qpeg: mark the init function as thread-safe and init cleanup capable

Reviewed-by: Anton Khirnov <anton@khirnov.net>
Signed-off-by: James Almer <jamrial@gmail.com>

libavcodec/qpeg.c

@@ -366,4 +366,6 @@ AVCodec ff_qpeg_decoder = {
     .decode         = decode_frame,
     .flush          = decode_flush,
     .capabilities   = AV_CODEC_CAP_DR1,
+    .caps_internal  = FF_CODEC_CAP_INIT_THREADSAFE |
+                      FF_CODEC_CAP_INIT_CLEANUP,
 };