Use relative path for portcheck.sh

Change-Id: I4acbfa453ef96d1fd9cfd652c30c6725bbd869b6
diff --git a/seba-in-a-box/Makefile b/seba-in-a-box/Makefile
index 8921620..26c3e63 100644
--- a/seba-in-a-box/Makefile
+++ b/seba-in-a-box/Makefile
@@ -51,7 +51,7 @@
 siab-1.0: $(M)/seba-1.0.0 $(M)/siab
 
 $(M)/setup:
-	sudo $(WORKSPACE)/cord/automation-tools/scripts/portcheck.sh
+	sudo $(MAKEDIR)/../scripts/portcheck.sh
 	mkdir -p $(M)
 	sudo apt update
 	sudo apt install -y httpie jq software-properties-common