packets: Fix userland implementation of set-field ipv6 addresses

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
ofprot-dpif.at: Fix races

Fix races in "ofproto-dpif - controller" test.

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
ofproto-dpif.at: Workaround races in megaflow tests

Avoid races in megaflow tests by sprinkling "sleep 1".

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
daemon.at: Fix stderr races

When spawning ovsdb-server in background, redirect stderr to /dev/null.
Otherwise, the banner output (eg. "ovsdb-server (Open vSwitch) 2.1.90")
can mess stderr of the following commands and make these tests fail.

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>
ofproto-dpif.at: Avoid races by sleeping

And add a comment.

Signed-off-by: YAMAMOTO Takashi <yamamoto@valinux.co.jp>
Signed-off-by: Ben Pfaff <blp@nicira.com>