Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20170607' into...

Merge remote-tracking branch 'remotes/juanquintela/tags/migration/20170607' into staging

migration/next for 20170607

# gpg: Signature made Wed 07 Jun 2017 10:02:01 BST
# gpg:                using RSA key 0xF487EF185872D723
# gpg: Good signature from "Juan Quintela <quintela@redhat.com>"
# gpg:                 aka "Juan Quintela <quintela@trasno.org>"
# Primary key fingerprint: 1899 FF8E DEBF 58CC EE03  4B82 F487 EF18 5872 D723

* remotes/juanquintela/tags/migration/20170607:
  qemu/migration: fix the double free problem on from_src_file
  ram: Make RAMState dynamic
  ram: Use MigrationStats for statistics
  ram: Move ZERO_TARGET_PAGE inside XBZRLE
  ram: Call migration_page_queue_free() at ram_migration_cleanup()
  ram: We only print throttling information sometimes
  ram: Unfold get_xbzrle_cache_stats() into populate_ram_info()

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