[M] Change in coreboot[main]: soc/mediatek: Add common implmentation to configure display

[Yu-Ping Wu (Code Review)]

Attention is currently required from: Hung-Te Lin, Paul Menzel, Yidi Lin.

Yu-Ping Wu has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/79776?usp=email )

Change subject: soc/mediatek: Add common implmentation to configure display
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Patch Set 2:

(1 comment)

File src/soc/mediatek/common/display.c:

https://review.coreboot.org/c/coreboot/+/79776/comment/20cba7f8_4bbaabed :
PS1, Line 42: 		if (panel->get_edid && panel->get_edid(panel) < 0)
> > And s can also be removed from panel. […]

I think we just need a local variable to store panel_serializable_data.

```
struct edid edid;

if (DISP_PATH_EDP) {
    ...
} else {
    panel_serializable_data mipi_data = {0};

if (panel->get_edid) {
        panel->get_edid(panel, &edid);  // Fills edid
    } else {
        get_mipi_panel_from_cbfs(&mipi_data);
        edid = mipi_data.edid;  // Or use pointer
    }

mtk_dsi_init(..., mipi_data->init);
}
```