Links to appropriate OpenThread RCP firmware for different adapters?

[Hedda]

Readme for Nerivec's similar zigbee-on-host project contains links to appropriate OpenThread RCP firmware compatible with a few common IEEE 802.15.4-based radio adapters. Might it be a good idea to have such links in this repo's readme or perhaps in a wiki?

• Nabu Casa's Silicon Labs firmware builder repository for ZBT-1/ZBT-2: https://github.com/NabuCasa/silabs-firmware-builder
• Nerivec's repo for third-party Silabs adapters: https://github.com/Nerivec/silabs-firmware-builder/releases
• Koenkk's repo for third-party Texas Instruments adapters: https://github.com/Koenkk/OpenThread-TexasInstruments-firmware/releases
• Discussion about Nordic Semiconductor (Nordic Semi) adapters: Test of Ziggurat with OpenThread RCP on Nordic Semiconductor (Nordic Semi) hardware? #32

Maybe add a disclaimer that downloding software and flashing firmware is done as the the users own risk, though it should be obvious.