build/ich9utils: simplify, fix error handling

errors weren't being handled inside a subshell

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

resources/scripts/build/module/ich9utils

@@ -2,7 +2,7 @@
 
 #  helper script: build ich9utils
 #
-#	Copyright (C) 2014, 2015, 2020 Leah Rowe <info@minifree.org>
+#	Copyright (C) 2014, 2015, 2020, 2023 Leah Rowe <info@minifree.org>
 #
 #    This program is free software: you can redistribute it and/or modify
 #    it under the terms of the GNU General Public License as published by
@@ -18,15 +18,19 @@
 #    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #
 
-# This script assumes that the current working directory is the root
-# of libreboot_src or libreboot git
-
 [ "x${DEBUG+set}" = 'xset' ] && set -v
 set -u -e
 
-printf "Build ich9utils\n"
-(
-cd "util/ich9utils/"
-make -j$(nproc)
-)
-printf "\n\n"
+main()
+{
+	printf "Build ich9utils\n"
+	make -j$(nproc) -C "util/ich9utils" || err "make"
+}
+
+err()
+{
+	printf "%s: %s\n" $0 $1
+	exit 1
+}
+
+main $@