hnm4: Use av_image_check_size

As done for all the other codecs not calling it indirectly.

CC: libav-stable@libav.org
Bug-Id: CID 1135770 / CID 1135771

libavcodec/hnm4video.c

@@ -22,6 +22,7 @@
 
 #include <string.h>
 
+#include "libavutil/imgutils.h"
 #include "libavutil/internal.h"
 #include "libavutil/intreadwrite.h"
 #include "libavutil/mem.h"
@@ -406,6 +407,7 @@ static int hnm_decode_frame(AVCodecContext *avctx, void *data,
 static av_cold int hnm_decode_init(AVCodecContext *avctx)
 {
     Hnm4VideoContext *hnm = avctx->priv_data;
+    int ret;
 
     if (avctx->extradata_size < 1) {
         av_log(avctx, AV_LOG_ERROR,
@@ -413,6 +415,10 @@ static av_cold int hnm_decode_init(AVCodecContext *avctx)
         return AVERROR_INVALIDDATA;
     }
 
+    ret = av_image_check_size(avctx->width, avctx->height, 0, avctx);
+    if (ret < 0)
+        return ret;
+
     hnm->version   = avctx->extradata[0];
     avctx->pix_fmt = AV_PIX_FMT_PAL8;
     hnm->width     = avctx->width;