Add board support for Seeed XIAO ESP32C6

[Maxwelltoo]

Description of Change

Add board support for Seeed XIAO ESP32C6.

Tests scenarios

I have tested my Pull Request on Arduino-esp32 core v3.0.0-alpha3 with Seeed XIAO ESP32C6 with basic examples(GPIO, ADC, SPI, Wire and WiFi).

[CLAassistant]

All committers have signed the CLA.

[github-actions]

	Messages
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👋 Hello Maxwelltoo, we appreciate your contribution to this project!

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[P-R-O-C-H-Y]

@Maxwelltoo Can you please sign CLA? Thanks :)