print/ghostscript9-agpl-*: Remove expired port

2023-12-31 print/ghostscript9-agpl-x11: Obsolete and unsupported upstream, consider using print/ghostscipt10
2023-12-31 print/ghostscript9-agpl-base: Obsolete and unsupported upstream, consider using print/ghostscipt10

Differential Revision: https://reviews.freebsd.org/D42376