graphics/tiffgt: Mark DEPRECATED

• There has been a newer version 4.6.0 released and it explicitly mentions the following: This version removes a big number of utilities that have suffered from lack of maintenance over the years and were the source of various reported security issues. See "Removed functionality" below for the list of removed utilities. Starting with libtiff v4.6.0, their source code, at this time, will still be available in the source distribution, but they will no longer be built by default, and issues related to them will no longer be accepted in the libtiff bug tracker. The only remaining supported TIFF tools are tiffinfo, tiffdump, tiffcp, tiffset and tiffsplit. Based on this I am marking this DEPRECATED
• Set to EXPIRE on 2023-10-13
• Add PORTSCOUT to skip version check