Merge remote-tracking branch 'remotes/dgilbert/tags/pull-migration-20180206a' into...

Migration pull 2018-02-06

This is based off Juan's last pull with a few extras, but
also removing:
   Add migration xbzrle test
   Add migration precopy test

As well as my normal test boxes, I also gave it a test
on a 32 bit ARM box and it seems happy (a Calxeda highbank)
and a big-endian power box.

Dave

# gpg: Signature made Tue 06 Feb 2018 15:33:31 GMT
# gpg:                using RSA key 0516331EBC5BFDE7
# gpg: Good signature from "Dr. David Alan Gilbert (RH2) <dgilbert@redhat.com>"
# Primary key fingerprint: 45F5 C71B 4A0C B7FB 977A  9FA9 0516 331E BC5B FDE7

* remotes/dgilbert/tags/pull-migration-20180206a:
  migration: incoming postcopy advise sanity checks
  migration: Don't leak IO channels
  migration: Recover block devices if failure in device state
  tests: Adjust sleeps for migration test
  tests: Create migrate-start-postcopy command
  tests: Add deprecated commands migration test
  tests: Use consistent names for migration
  tests: Consolidate accelerators declaration
  tests: Remove deprecated migration tests commands
  migration: Drop current address parameter from save_zero_page()
  migration: use s->threshold_size inside migration_update_counters
  migration/savevm.c: set MAX_VM_CMD_PACKAGED_SIZE to 1ul << 32
  migration: Route errors down through migration_channel_connect
  migration: Allow migrate_fd_connect to take an Error *

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