Claude review: drm/rockchip: dw_hdmi: avoid direct dereference of phy->dev.of_node

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

Patch Review

Replaces `hdmi->phy->dev.of_node` with a DT phandle lookup to get the PHY's OF node for clock provider resolution. The refactoring uses:
```c
index = of_property_match_string(np, "phy-names", "hdmi");
if (index >= 0) {
    if (!of_parse_phandle_with_args(np, "phys", "#phy-cells", index, &clkspec)) {
        hdmi->hdmiphy_clk = of_clk_get_from_provider(&clkspec);
        of_node_put(clkspec.np);
```

This is a clean approach. The original code checked `if (hdmi->phy)` whereas the new code checks `if (index >= 0)` — these should be equivalent since `hdmi->phy` comes from the same DT property lookup. The `of_node_put(clkspec.np)` is correctly added (the original code via `hdmi->phy->dev.of_node` didn't need it since it was a borrowed reference). No issues.

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Generated by Claude Code Patch Reviewer