reflect name change of some of the variables in setupVars

automated install/basic-install.sh

@@ -817,6 +817,11 @@ installPihole() {
 }
 
 updatePihole() {
+    # Refactoring of install script has changed the name of a couple of variables. Sort them out here.
+    sed -i 's/IPv4addr/IPv4_address/g' ${setupVars}
+    sed -i 's/piholeIPv6/IPv6_address/g' ${setupVars}
+    # Source ${setupVars} for use in the rest of the functions.
+    . ${setupVars}
 	# Install base files and web interface
 	installScripts
 	installConfigs
@@ -868,7 +873,6 @@ update_dialogs(){
 		case ${UpdateCmd} in
             Update)
                 echo "::: Updating existing install"
-                . ${setupVars}
                 useUpdateVars=true
                 ;;
             Install)