Merge remote-tracking branch 'remotes/otubo/tags/pull-seccomp-20200915' into staging

seccomp branch queue

# gpg: Signature made Tue 15 Sep 2020 11:58:27 BST
# gpg:                using RSA key D67E1B50937486B40723DBABDF32E7C0F0FFF9A2
# gpg:                issuer "otubo@redhat.com"
# gpg: Good signature from "Eduardo Otubo (Senior Software Engineer) <otubo@redhat.com>" [full]
# Primary key fingerprint: D67E 1B50 9374 86B4 0723  DBAB DF32 E7C0 F0FF F9A2

* remotes/otubo/tags/pull-seccomp-20200915:
  seccomp: fix killing of whole process instead of thread

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>