build/boot/*: merge all logic into one script

for the first time ever, this is a single script.
with recent simplifications in how variables are
handled, and techniques i've developed during
auditing, it's now feasible design-wise for this
to be a single script, without a helper script.

Signed-off-by: Leah Rowe <leah@libreboot.org>

include/boot.sh

@@ -1,55 +0,0 @@
-# SPDX-License-Identifier: GPL-3.0-or-later
-# SPDX-FileCopyrightText: 2022 Caleb La Grange <thonkpeasant@protonmail.com>
-# SPDX-FileCopyrightText: 2022 Ferass El Hafidi <vitali64pmemail@protonmail.com>
-# SPDX-FileCopyrightText: 2023 Leah Rowe <leah@libreboot.org>
-
-eval "$(setvars "" first board boards _displaymode _payload _keyboard targets)"
-
-main()
-{
-	[ $# -lt 1 ] && usage && err "target not specified"
-
-	while [ $# -gt 0 ]; do
-		case ${1} in
-		help) usage && exit 0 ;;
-		list) listitems config/coreboot && exit 0 ;;
-		-d) _displaymode="${2}" ;;
-		-p) _payload="${2}" ;;
-		-k) _keyboard="${2}" ;;
-		all)
-			boards="$(listitems config/coreboot)"
-			shift && continue ;;
-		*)
-			boards="${1} ${boards}"
-			shift && continue ;;
-		esac
-		shift 2
-	done
-
-	check_target
-	prepare_target
-}
-
-usage()
-{
-	cat <<- EOF
-	USAGE:	./build boot roms target
-	To build *all* boards, do this: ./build boot roms all
-	To list *all* boards, do this: ./build boot roms list
-	
-	Optional Flags:
-	-d: displaymode
-	-p: payload
-	-k: keyboard layout
-
-	Example commands:
-		./build boot roms x60
-		./build boot roms x200_8mb x60
-		./build boot roms x60 -p grub -d corebootfb -k usqwerty
-
-	possible values for 'target':
-	$(listitems "config/coreboot")
-
-	Refer to the ${projectname} documentation for more information.
-	EOF
-}