Add OUI to tplink diagnostics (#97646)

* Add OUI to tplink diagnostics

The main reason discovery does not work for new devices is we
are missing the OUI. Since we redact the whole mac address in
the diagnostics, this makes it difficult to fix. We now include
the OUI in the diagnostics

* fix: use cached mac

* fix: tests

tests/components/tplink/test_diagnostics.py

@@ -14,17 +14,19 @@ from tests.typing import ClientSessionGenerator
 
 
 @pytest.mark.parametrize(
-    ("mocked_dev", "fixture_file", "sysinfo_vars"),
+    ("mocked_dev", "fixture_file", "sysinfo_vars", "expected_oui"),
     [
         (
             _mocked_bulb(),
             "tplink-diagnostics-data-bulb-kl130.json",
             ["mic_mac", "deviceId", "oemId", "hwId", "alias"],
+            "AA:BB:CC",
         ),
         (
             _mocked_plug(),
             "tplink-diagnostics-data-plug-hs110.json",
             ["mac", "deviceId", "oemId", "hwId", "alias", "longitude_i", "latitude_i"],
+            "AA:BB:CC",
         ),
     ],
 )
@@ -34,6 +36,7 @@ async def test_diagnostics(
     mocked_dev: SmartDevice,
     fixture_file: str,
     sysinfo_vars: list[str],
+    expected_oui: str | None,
 ):
     """Test diagnostics for config entry."""
     diagnostics_data = json.loads(load_fixture(fixture_file, "tplink"))
@@ -58,3 +61,5 @@ async def test_diagnostics(
     sysinfo = last_response["system"]["get_sysinfo"]
     for var in sysinfo_vars:
         assert sysinfo[var] == "**REDACTED**"
+
+    assert result["oui"] == expected_oui