Add comment to fwup script
#!/usr/bin/env bash
+# This script is only used on Windows installations to make invocations to fwup
+# from within the Windows Subsystem for Linux run fwup.exe. WSL doesn't allow
+# access to SDCards for Linux programs, but if fwup.exe is run, then the SDCard
+# programming part works.
+
FWUP_LOCATION="$(dirname "$(realpath "$0")")"
"$FWUP_LOCATION/fwup.exe" "$@"
