x86: preinit: use board_name on Sm Super Servers

Supermicro puts "Super Server" into their product_name DMI value
for a whole slew of products, making this value about as useful
as not having been filled in at all.  Instead, fall back on the
board_name instead.

Signed-off-by: Philip Prindeville <philipp@redfish-solutions.com>

target/linux/x86/base-files/lib/preinit/01_sysinfo

@@ -17,7 +17,14 @@ do_sysinfo_x86() {
 
 	for file in product_name board_name; do
 		product="$(cat /sys/devices/virtual/dmi/id/$file 2>/dev/null)"
-		[ -n "$product" ] && break
+		case "$vendor:$product" in
+		"Supermicro:Super Server")
+			continue
+			;;
+		?*:?*)
+			break
+			;;
+		esac
 	done
 
 	[ -n "$vendor" -a -n "$product" ] || return