avformat/http: cookie path attribute should be optional not compulsory

The path attribute in the Set-Cookie header is optional but treated by ffmpeg as being compulsory.
Signed-off-by: Michael J. Walsh <mjfwalsh@gmail.com>
Signed-off-by: Marton Balint <cus@passwd.hu>

libavformat/http.c

@@ -1293,9 +1293,9 @@ static int get_cookies(HTTPContext *s, char **cookies, const char *path,
                 goto skip_cookie;
         }
 
-        // ensure this cookie matches the path
+        // if a cookie path is provided, ensure the request path is within that path
         e = av_dict_get(cookie_params, "path", NULL, 0);
-        if (!e || av_strncasecmp(path, e->value, strlen(e->value)))
+        if (e && av_strncasecmp(path, e->value, strlen(e->value)))
             goto skip_cookie;
 
         // cookie parameters match, so copy the value