kernel/Makefile wrote the boot arguments with printf '$(KERNEL_ARGS)\n', so
arguments starting with '-' were taken for an option -- "printf: Illegal
option --", the build stops; the Makefile's own documented example,
KERNEL_ARGS="--doe --log-level=info", hit it -- and a '%' in them would be a
conversion. Now printf '%s\n' '$(KERNEL_ARGS)', as the board images already
write theirs, at all four places (the amd64, aarch64 and riscv64 qemu
recipes, and qemu-esp).
Red: the stick's increment 2 sessions with KERNEL_ARGS=--log-level=info
failed in make. Green: amd64 203627, aarch64 203833, riscv64 204237 --
starforth.cfg holds "--log-level=info" and the boot shows INFO lines after
POST. Accepted: 214300, 214507, 214911; test-32 0 failures.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
