backend/drm: make serial optional
The EDID 1.4 spec says that the serial number is optional:
If this field is not used, then enter “00h, 00h, 00h, 00h”.
Leave the wlr_output.serial field NULL in that case, and hide it from the output description.
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The EDID 1.4 spec says that the serial number is optional:
If this field is not used, then enter “00h, 00h, 00h, 00h”.
Leave the wlr_output.serial field NULL in that case, and hide it from the output description.