avcodec/flac_parser: Use sizeof(variable) instead of sizeof(type)

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/flac_parser.c

@@ -182,7 +182,7 @@ static int find_headers_search_validate(FLACParseContext *fpc, int offset)
             size++;
         }
 
-        *end_handle = av_mallocz(sizeof(FLACHeaderMarker));
+        *end_handle = av_mallocz(sizeof(**end_handle));
         if (!*end_handle) {
             av_log(fpc->avctx, AV_LOG_ERROR,
                    "couldn't allocate FLACHeaderMarker\n");