Update to new xen-{evtchn,gnt} ocamlfind packages

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

Signed-off-by: David Scott <dave.scott@eu.citrix.com>
Merge pull request #6 from djs55/add-oasis

Update to new xen-{evtchn.gnt}