xen: remove now-unused secondary function header

The old `buildXenPackage` builder was a curried function that had to be
completed with a second call with attributes like `pname` and `version`.
As it is no longer necessary to call a generic builder to build custom
variants of Xen, the package must comply with the `by-name` checks, which
include the requirement that all `package.nix` files in this directory
hierarchy resolve to a derivation. (and not a function)

Signed-off-by: Fernando Rodrigues <alpha@sigmasquadron.net>

0 files changed, 0 insertions, 0 deletions