fix: mark openmsx system roms as found by sha1

openMSX reaches a ROM in share/systemroms through its file pool by SHA1
alone. A filename is only looked up beside the machine's XML
(src/memory/Rom.cc:121-170, HardwareConfig.cc:279-280,
FileContext.cc:152-156 at a557de7b). The labels read as names the core
opens, and the export added 15 of them to KNULLI and 2 to Batocera.

emulators/openmsx.yml

@@ -10,6 +10,7 @@ version_basis:
   tag: "RELEASE_22_0_RC2"
   distance: 0
 display_name: "MSX / ColecoVision / Spectravideo (openMSX)"
+found_by: content
 cores:
   - openmsx
 systems:
@@ -29,7 +30,9 @@ notes: |
 
   ROM resolution via FilePool (src/file/FilePool.cc, FilePoolCore.cc):
   searches configured directories for files matching SHA1 checksums.
-  Filenames are secondary hints, while SHA1 is the primary lookup key.
+  A ROM in share/systemroms is reached by its SHA1 alone: a filename is only
+  looked up beside the machine's XML (src/memory/Rom.cc:121-170,
+  src/config/HardwareConfig.cc:279-280, src/file/FileContext.cc:152-156).
   Files may be gzipped or individually zipped.
   Each user data directory contributes share/systemroms, scanned
   recursively (src/file/FilePool.cc:27, src/file/FilePoolCore.cc:369-385). RetroBat

tests/test_audit_regressions.py

@@ -6924,5 +6924,25 @@ class Dev9FilesAreReadFromTheWorkingDirectory(unittest.TestCase):
         self.assertEqual(unset, [])
 
 
+class OpenMsxSystemRomsAreFoundBySha1(unittest.TestCase):
+    """openMSX reaches a ROM in share/systemroms through the file pool by
+    SHA1 alone, a filename being looked up only beside the machine's XML
+    (src/memory/Rom.cc:121-170). Read as names the core opens, the labels
+    were added to the KNULLI and Batocera exports."""
+
+    def test_no_systemrom_label_reads_as_a_name(self):
+        import yaml
+
+        from validation import opens_by_name
+
+        profile = yaml.safe_load((ROOT / "emulators" / "openmsx.yml").read_text())
+        named = [
+            entry["name"] for entry in profile["files"]
+            if "share/systemroms/" in str(entry.get("path"))
+            and opens_by_name(entry, profile)
+        ]
+        self.assertEqual(named, [])
+
+
 if __name__ == "__main__":
     unittest.main()