Replace deprecated FF_I_TYPE with AV_PICTURE_TYPE_I in v308 and yuv4.

Found-by: Paul B Mahol

libavcodec/v308dec.c

@@ -62,7 +62,7 @@ static int v308_decode_frame(AVCodecContext *avctx, void *data,
     }
 
     pic->key_frame = 1;
-    pic->pict_type = FF_I_TYPE;
+    pic->pict_type = AV_PICTURE_TYPE_I;
 
     y = pic->data[0];
     u = pic->data[1];

libavcodec/v308enc.c

@@ -56,7 +56,7 @@ static int v308_encode_frame(AVCodecContext *avctx, uint8_t *buf,
 
     avctx->coded_frame->reference = 0;
     avctx->coded_frame->key_frame = 1;
-    avctx->coded_frame->pict_type = FF_I_TYPE;
+    avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
 
     y = pic->data[0];
     u = pic->data[1];

libavcodec/yuv4dec.c

@@ -60,7 +60,7 @@ static int yuv4_decode_frame(AVCodecContext *avctx, void *data,
     }
 
     pic->key_frame = 1;
-    pic->pict_type = FF_I_TYPE;
+    pic->pict_type = AV_PICTURE_TYPE_I;
 
     y = pic->data[0];
     u = pic->data[1];

libavcodec/yuv4enc.c

@@ -50,7 +50,7 @@ static int yuv4_encode_frame(AVCodecContext *avctx, uint8_t *buf,
 
     avctx->coded_frame->reference = 0;
     avctx->coded_frame->key_frame = 1;
-    avctx->coded_frame->pict_type = FF_I_TYPE;
+    avctx->coded_frame->pict_type = AV_PICTURE_TYPE_I;
 
     y = pic->data[0];
     u = pic->data[1];