cleanup: use $OPENSHIFT_INSTALLER path

The ocp directory doesn't always have the binary present.  For example,
the cleanup commands will fail when openshift-installer is built from
git.

Author: honza

ocp_cleanup.sh

@@ -13,8 +13,8 @@ if sudo systemctl is-active fix_certs.timer; then
 fi
 
 if [ -d ${OCP_DIR} ]; then
-    ${OCP_DIR}/openshift-install --dir ${OCP_DIR} --log-level=debug destroy bootstrap
-    ${OCP_DIR}/openshift-install --dir ${OCP_DIR} --log-level=debug destroy cluster
+    $OPENSHIFT_INSTALLER --dir ${OCP_DIR} --log-level=debug destroy bootstrap
+    $OPENSHIFT_INSTALLER --dir ${OCP_DIR} --log-level=debug destroy cluster
     rm -rf ${OCP_DIR}
 fi