Merge remote-tracking branch 'remotes/rth/tags/pull-axp-20170228' into staging

Enable MTTCG for Alpha guest

# gpg: Signature made Tue 28 Feb 2017 00:43:17 GMT
# gpg:                using RSA key 0xAD1270CC4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"
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* remotes/rth/tags/pull-axp-20170228:
  target/alpha: Enable MTTCG by default
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

configure

@@ -5894,6 +5894,7 @@ case "$target_name" in
     TARGET_BASE_ARCH=i386
   ;;
   alpha)
+    mttcg="yes"
   ;;
   arm|armeb)
     TARGET_ARCH=arm

target/alpha/cpu.h

@@ -28,6 +28,9 @@
 
 #define CPUArchState struct CPUAlphaState
 
+/* Alpha processors have a weak memory model */
+#define TCG_GUEST_DEFAULT_MO      (0)
+
 #include "exec/cpu-defs.h"
 
 #include "fpu/softfloat.h"