abuild: break early if building tools fails

Change-Id: I8da04df024a31c780b924a586d056a5351845153
Signed-off-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-on: http://review.coreboot.org/4773
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

util/abuild/abuild

@@ -613,7 +613,7 @@ build_all_targets()
 	if [ "$enable_blobs" = "true" ]; then
 		echo "CONFIG_USE_BLOBS=y" > $TMPCFG
 	fi
-	make -j $cpus DOTCONFIG=$TMPCFG obj=coreboot-builds/temp objutil=coreboot-builds/sharedutils tools
+	make -j $cpus DOTCONFIG=$TMPCFG obj=coreboot-builds/temp objutil=coreboot-builds/sharedutils tools || exit 1
 	rm -rf coreboot-builds/temp $TMPCFG
 	for VENDOR in $( vendors ); do
 		for MAINBOARD in $( mainboards $VENDOR ); do