Support for Waveshare ILI9486

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

Pulling most of this info from https://github.com/esphome/feature-requests/issues/1102 - opened by @EpicLPer - which was closed after adding the xpt2046 but this is a request to support the display - ili9486

In the Dev version of ESPHome support for standard 320x240 ILI9341 based displays has recently been added, see #51. A big thanks to the devs for this already :)
Waveshare has a 3.5" (480x320) and 4" (800×480) version based on the same controller (and/or XPT2046? Not entirely sure where the difference lays here) which sadly does not work with this.

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

I tried the standard ILI9486 M5stack and TFT_2.4 options already but got no usable output, however the display does seem to read SPI data since, on M5stack, it constantly tries to refresh the display but seems to fail and on TFT_2.4 it very slightly flickers the whole screen. In both cases it never draws anything on screen tho.

**Additional context**

Waveshare offers their Arduino libraries for both TFT versions here: https://github.com/ImpulseAdventure/Waveshare_ILI9486
I also found another library by „GoodTFT“ which also seems to offer one here: https://github.com/goodtft/LCD-show

There was also a PR to support this display opened by MasterTim17 that was not merged to main. https://github.com/esphome/esphome/pull/1523

Review PR #1523 and the referenced Waveshare_ILI9486 and LCD-show libraries first, then compare their behavior with ESPHome's existing ILI9341 support. Done means the Waveshare 3.5-inch 480x320 and 4-inch 800x480 displays produce usable output.

Written by the indexing model from the issue text.