Make parse_inputs() return AVERROR(EINVAL) rather than -1 in case the

link label parsed by parse_link_name() is invalid.

Originally committed as revision 25696 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavfilter/graphparser.c

@@ -249,7 +249,7 @@ static int parse_inputs(const char **buf, AVFilterInOut **curr_inputs,
         AVFilterInOut *match;
 
         if (!name)
-            return -1;
+            return AVERROR(EINVAL);
 
         /* First check if the label is not in the open_outputs list */
         match = extract_inout(name, open_outputs);