xenserver-core: 'kernel' should be 'linux-image'

Signed-off-by: David Scott <dave.scott@citrix.com>
Add package containing missing header

Signed-off-by: David Scott <dave.scott@citrix.com>
Update ocaml-lambda-term following feedback from @euanh

Signed-off-by: David Scott <dave.scott@citrix.com>
xen-missing-headers: fix the package

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