Merge remote-tracking branch 'remotes/berrange-gitlab/tags/tls-deps-pull-request...

Hide build time dependancy on gnutls fom non-crypto code

# gpg: Signature made Wed 30 Jun 2021 12:18:47 BST
# gpg:                using RSA key DAF3A6FDB26B62912D0E8E3FBE86EBB415104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>" [full]
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>" [full]
# Primary key fingerprint: DAF3 A6FD B26B 6291 2D0E  8E3F BE86 EBB4 1510 4FDF

* remotes/berrange-gitlab/tags/tls-deps-pull-request:
  crypto: Make QCryptoTLSCreds* structures private
  ui/vnc: Use qcrypto_tls_creds_check_endpoint()
  migration/tls: Use qcrypto_tls_creds_check_endpoint()
  chardev/socket: Use qcrypto_tls_creds_check_endpoint()
  qemu-nbd: Use qcrypto_tls_creds_check_endpoint()
  block/nbd: Use qcrypto_tls_creds_check_endpoint()
  crypto/tlscreds: Introduce qcrypto_tls_creds_check_endpoint() helper

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