build system: fix for dash

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

scripts/gen_build_files.sh

@@ -18,14 +18,17 @@ generate()
 	local src="$1" dst="$2" header="$3" insert="$4"
 	#chk "${dst}"
 	(
-		echo "${header}"
+		# need to use printf: different shells have inconsistent
+		# rules re handling of "\n" in their params,
+		# and ${insert} definitely contains "\n"
+		printf "%s\n" "${header}"
 		if grep -qs '^INSERT$' "${src}"; then
 			sed -n '1,/^INSERT$/p' "${src}"
-			echo "${insert}"
+			printf "%s\n" "${insert}"
 			sed -n '/^INSERT$/,$p' "${src}"
 		else
 			if [ -n "${insert}" ]; then
-				echo "ERROR: INSERT line missing in: ${src}" 1>&2
+				printf "%s\n" "ERROR: INSERT line missing in: ${src}" 1>&2
 			fi
 			cat "${src}"
 		fi