Document supported VGA to HDMI adapter

Fixes #76

README.md

@@ -25,6 +25,8 @@ Turn your Raspberry Pi into a browser-based KVM.
 * [microSD card](https://amzn.to/2VH0RcL) (Class 10, 8 GB or larger)
 * [HDMI to HDMI cable](https://amzn.to/3gnlZwj)
   * Or \[other\] to HDMI, depending on how your target machine displays output.
+* (Optional) [VGA to HDMI Adapter](https://amzn.to/30SZWYh)
+  * If your target computer has VGA output, the above adapter is [confirmed to work](https://github.com/mtlynch/tinypilot/issues/76#issuecomment-664736402) with TinyPilot.
 
 See ["TinyPilot: Build a KVM Over IP for Under $100"](https://mtlynch.io/tinypilot/#how-to-build-your-own-tinypilot) for a more detailed tutorial on how to assemble these parts to create a TinyPilot.