external: add support for rados namespace for rbd ec pools

currently addded the support for rados namesapce
for rbd ec pools upstream

closes: https://github.com/rook/rook/issues/13633

Signed-off-by: parth-gr <partharora1010@gmail.com>
(cherry picked from commit adf40b1944)

deploy/examples/create-external-cluster-resources.py

@@ -1353,6 +1353,8 @@ class RadosJSON:
 
     def validate_rados_namespace(self):
         rbd_pool_name = self._arg_parser.rbd_data_pool_name
+        if self._arg_parser.rbd_metadata_ec_pool_name:
+            rbd_pool_name = self._arg_parser.rbd_metadata_ec_pool_name
         rados_namespace = self._arg_parser.rados_namespace
         if rados_namespace == "":
             return