Revert "selinux: Add fcontext for core dumps"

The problem is that the kernel at build time does not know about the
label virt_cache_t and fails to relabel the whole fs.

The relabeling of the directory needs to happen at runtime.

This reverts commit 88ceb280bb3c21a9aa252f841eaf4267a2279b40.

Change-Id: Ie486ef0afcbad4acd92333d5f530b1705efaeb20
Signed-off-by: Fabian Deutsch <fabiand@fedoraproject.org>