meta-agl-ic-container: fix packagegroup-agl-core-selinux-guest

meta-agl-ic-container: fix packagegroup-agl-core-selinux-guest

packagegroup-agl-core-selinux-guest now triggers a packaging QA
check due to it being marked as allarch and pulling in libraries
that get renamed by the Debian library renaming logic used by
upstream.  To fix, follow what is done by the similar packagegroups
in meta-selinux and not use packagegroup.bbclass.

Bug-AGL: SPEC-5123

Change-Id: I1391977d5db3aad3d4e87ff8d043a3bb26b7074a
Signed-off-by: Scott Murray <scott.murray@konsulko.com>
(cherry picked from commit c7c181b3986803e49844e1e371643b6545e8681e)