Merge remote-tracking branch 'remotes/berrange/tags/qcrypto-fixes-pull-20151022-2...

Merge remote-tracking branch 'remotes/berrange/tags/qcrypto-fixes-pull-20151022-2' into staging

Merge qcrypto-fixes 2015/10/22

# gpg: Signature made Thu 22 Oct 2015 19:03:45 BST using RSA key ID 15104FDF
# gpg: Good signature from "Daniel P. Berrange <dan@berrange.com>"
# gpg:                 aka "Daniel P. Berrange <berrange@redhat.com>"

* remotes/berrange/tags/qcrypto-fixes-pull-20151022-2:
  configure: avoid polluting global CFLAGS with tasn1 flags
  crypto: add sanity checking of plaintext/ciphertext length
  crypto: don't let builtin aes crash if no IV is provided
  crypto: allow use of nettle/gcrypt to be selected explicitly

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