x86/cpu/topology: Remove topology_max_die_per_package()

JIRA: https://issues.redhat.com/browse/RHEL-79821


Upstream Status: RHEL-only

In order to allow a smooth transition, topology_max_die_per_package() was
provided even as part of RHEL commit b2d6cca8.  As the function is no
longer utilized it should be removed.

Signed-off-by: David Arcari <darcari@redhat.com>