Appease OASIS by placing code with different buildepends in different dirs

Unfortunately if we have both Xen-specific (Build$: flag(xenctrl)) and
other code in the same dir, the other code is 'ocamldep'ped with the
builddepends from the Xen-specific code too, which isn't present.

The solution seems to be to separate everything that's even slightly
different into a separate directory.

Signed-off-by: David Scott <dave.scott@citrix.com>
Regenerate OASIS

Signed-off-by: David Scott <dave.scott@citrix.com>