feat: collect the tyrian files emuelec declares

EmuELEC declares 19 files of the Tyrian 2.1 distribution (setup.ini,
netterm.int, the net*.pcx screens...) that bios/ did not hold. They
resolved only at the data directory step, against data/opentyrian, the
cache refresh_data_dirs.py fills from the opentyrian-data.zip asset. verify
gave 544/572 in a checkout holding that cache and 525/572 in one without
it, for the same commit.

The 19 files are taken from the freeware tyrian21.zip (camanis.net, sha1
29827de9), each equal to the cached copy. netset.pcx and tyrset.pcx are
the same bytes under two names, so the folder joins NODEDUP_DIRS. A test
resolves every platform entry with the data directory caches present and
fails on any that only a cache answers.

scripts/dedup.py

@@ -70,6 +70,9 @@ NODEDUP_DIRS = {
     # MAME's support trees (hash, plugins) are read by path as a whole, and
     # two MAME versions share most of their software lists byte for byte.
     "mame",
+    # The Tyrian 2.1 distribution ships netset.pcx and tyrset.pcx with the
+    # same bytes, and EmuELEC places both names under ports/opentyrian/.
+    "opentyrian",
 }