Claude review: drm/amd: fix HDMI signal type for EDID overrides

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

**Potential problem with `populate_hdmi_info_from_connector()`:** In `dm_helpers_parse_edid_caps()`, when the code forces `edid_caps->edid_hdmi = true` due to the override, it then calls:
```c
if (edid_caps->edid_hdmi)
    populate_hdmi_info_from_connector(&connector->display_info.hdmi, edid_caps);
```
But `connector->display_info.hdmi` was populated from the *overridden* EDID (which lacks HDMI VSDB). This means the HDMI info structure will contain zeros/defaults, which could lead to issues downstream (e.g. missing audio capabilities, incorrect infoframe data). The patch should document this limitation or handle it.

**Duplicated logic:** The connector-type check `(connector->connector_type == DRM_MODE_CONNECTOR_HDMIA || connector->connector_type == DRM_MODE_CONNECTOR_HDMIB)` appears in two places. A small helper like `drm_connector_is_hdmi_type()` would reduce duplication, though this is minor.

**Signal type for HDMIB:** Setting `SIGNAL_TYPE_HDMI_TYPE_A` for `DRM_MODE_CONNECTOR_HDMIB` connectors is technically incorrect - HDMI Type B uses a different physical connector. In practice HDMIB is essentially unused, so this is unlikely to cause real issues, but it's worth noting.

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Generated by Claude Code Patch Reviewer