Add Interface_DisplayPort lib with PI3DPX1203BZLEX symbol

[eclecticc]

Create an Interface_DisplayPort library starting with a symbol for Diodes Inc PI3DPX1203BZLEX https://www.diodes.com/assets/Datasheets/PI3DPX1203B.pdf

The associated footprint is in https://github.com/KiCad/kicad-footprints/pull/1979

Note that the VDD pins are not stacked because Diodes recommends putting a decoupling cap on each one.

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