avformat/nutdec: Return error on EOF from get_str()

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
(cherry picked from commit 6bbb2f8f)
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavformat/nutdec.c

@@ -51,6 +51,8 @@ static int get_str(AVIOContext *bc, char *string, unsigned int maxlen)
     if (maxlen)
         string[FFMIN(len, maxlen - 1)] = 0;
 
+    if (bc->eof_reached)
+        return AVERROR_EOF;
     if (maxlen == len)
         return -1;
     else