Support for the 7.3inch E Ink Spectra 6 (E6)

**Describe the problem you have/What new integration you would like**

Support for the 7.3inch E Ink Spectra 6 (E6)
https://www.waveshare.com/7.3inch-e-paper-hat-e.htm

**Please describe your use case for this integration and alternatives you've tried:**

There is already 7.30in-f - 7.3in 7-color display (black, white, red, yellow, blue, green, and orange)
So it should be very simple to adapt. I think inverted: true is also needed. So its just a naming i think

**Additional context**

Start by finding the existing 7.30in-f support for the 7-color display and compare it with the Waveshare 7.3inch E Ink Spectra 6 (E6) specification at the linked product page. Add the E6 naming and verify whether inverted: true is required; done means the new display is recognized and works like the existing 7.30in-f integration.

Written by the indexing model from the issue text.