Add a short explanation to Zadig the troubleshooting section (#7110)

Add a short explanation to Zadig the troubleshooting section (#7110)

* Add a short explanation to the troubleshooting section

While translating I noticed that the troubleshooting section could use a
little bit more explanation. @Yanfali was so kind to chime in on this on
discord and explained that this was ment for people who accidently
forget to put their board in bootloader mode, so I added this as a
possible common mistake.

Also fixed the spelling of Msys2 to MSYS2 and Halfkay to HalfKay as
these are the official spellings they use themselves.

* Update driver_installation_zadig.md

* Update driver_installation_zadig.md

English is hard.

* Update docs/driver_installation_zadig.md

Co-Authored-By: fauxpark <fauxpark@gmail.com>
* Update docs/driver_installation_zadig.md

Co-Authored-By: fauxpark <fauxpark@gmail.com>