Add support for ESP32-S2 & ESP32-S3 boards

[Hans0lo]

These two Espressif chips offer native USB support.
But when attempting to use this library, the following error is shown:

WARNING: library MIDIUSB claims to run on avr, sam, samd architecture(s) and may be incompatible with your current board which runs on esp32 architecture(s).

any chance there will be support for these boards?

Additional context

Additional requests

• Add support for ESP32-S2 & ESP32-S3 boards #95 (comment)
• Add support for ESP32-S2 & ESP32-S3 boards #95 (comment)

[rigr]

BPI-Leaf-S3 for example should support USB MIDI but is not yet supported by this library. Would be great!

Any news about this topic?