Merge remote-tracking branch 'remotes/rth/tags/tcg-pull-20150316' into staging

tcg opt fix for or x,a,a

# gpg: Signature made Mon Mar 16 15:47:19 2015 GMT using RSA key ID 4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"

* remotes/rth/tags/tcg-pull-20150316:
  tcg/optimize: Handle or r,a,a with constant a

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