tools/libxc: Migration v2 compatibility for unmodified libxl
These changes cause migration v2 to behave similarly enough to legacy
migration to function for HVM guests under an unmodified xl/libxl.
The migration v2 work for libxl will fix the layering issues with the
toolstack and qemu records, at which point this patch will be unneeded.
It is however included here for people wishing to experiment with migration v2
ahead of the libxl work.
Signed-off-by: Andrew Cooper <andrew.cooper3@citrix.com>
Acked-by: Ian Campbell <Ian.Campbell@citrix.com>