don't include memtest by default. make it a board.cfg option

resources/scripts/build/boot/roms_helper

@@ -59,6 +59,7 @@ payload_seabios="n"
 payload_seabios_withgrub="n" # i386-coreboot grub accessible from SeaBIOS boot menu
 payload_tianocore="n"
 seabios_opromloadonly="0"
+payload_memtest="n"
 # Override the above defaults using board.cfg
 source "resources/coreboot/${board}/board.cfg"
 if [ "${cbtree}" = "undefined" ]; then
@@ -74,6 +75,10 @@ if [ "${seabios_opromloadonly}" != "0" ] && \
 		[ "${seabios_opromloadonly}" != "1" ]; then
 	seabios_opromloadonly="0"
 fi
+if [ "${payload_memtest}" != "n" ] && \
+		[ "${payload_memtest}" != "y" ]; then
+	payload_memtest="n"
+fi
 if [ "${payload_grub_withseabios}" = "y" ] \
 		|| [ "${payload_grub_withtianocore}" = "y" ]; then
 	payload_grub="y"
@@ -104,9 +109,11 @@ if [ "${payload_grub}" != "y" ] && [ "${payload_seabios}" != "y" ] \
 	done
 fi
 
+if [ "${payload_memtest}" = "y" ]; then
 	if [ ! -f "memtest86plus/memtest" ]; then
 		./build module memtest86plus
 	fi
+fi
 
 romdir="bin/${board}"
 cbdir="coreboot/${board}"
@@ -398,7 +405,7 @@ mkRoms() {
 		mkRomWithTianocoreOnly "${corebootrom}" "${initmode}"
 	fi
 
-	if [ "${displaymode}" = "txtmode" ]; then
+	if [ "${displaymode}" = "txtmode" ] && [ "${payload_memtest}" = "y" ]; then
 		"${cbfstool}" "${corebootrom}" add-payload -f memtest86plus/memtest -n img/memtest -c lzma
 	fi