When a connection upgrade is requested and when the
request sent an error reply, it happened most often
that a segmentation fault occured.
The patch applied here is a backport from the
upstream (see https://gnunet.org/git/libmicrohttpd.git/
commit b4216c60fdb5b48f6cfec416301fc63a1167e6cd).
Change-Id: I6847550ba2c4fc24d5caf8912ac6d5ac89ae01fb
Signed-off-by: José Bollo <jose.bollo@iot.bzh>
Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Armin Kuster <akuster808@gmail.com>