Remove VxFlex OS credentials from connection_properties

VxFlex OS password is not stored in block_device_mapping table.
Instead of this passwords are stored in separate file and are
retrieved during each attach/detach operation.

The stable/pike branch is in Extended Maintenance mode and is no
longer released from.  If you decide to apply this patch to your
deployment, you must make a corresponding change to the os-brick
library.  You can find the os-brick patch for stable/pike here:
    https://review.opendev.org/#/c/733615

Additionally, you must deploy a new configuration file on compute
nodes, cinder nodes, and anywhere you would perform a volume
attachment in your deployment.  See the documentation change on
this patch for details about the new config file.

See OSSN-0086 for more information about this change:
    https://wiki.openstack.org/wiki/OSSN/OSSN-0086

Change-Id: I975922b2ac951988e51743cd9f2f6f76be520840
Closes-Bug: #1823200

cinder/volume/drivers/dell_emc/scaleio/driver.py

@@ -144,9 +144,10 @@ class ScaleIODriver(driver.VolumeDriver):
         2.0.1: Added support for SIO 1.3x in addition to 2.0.x
         2.0.2: Added consistency group support to generic volume groups
         2.0.3: Added cache for storage pool and protection domains info
+        2.0.3.1: Fix for Bug #1823200. See OSSN-0086 for details.
     """
 
-    VERSION = "2.0.3"
+    VERSION = "2.0.3.1"
     # ThirdPartySystems wiki
     CI_WIKI_NAME = "EMC_ScaleIO_CI"
 
@@ -220,8 +221,7 @@ def __init__(self, *args, **kwargs):
             'serverIP': self.server_ip,
             'serverPort': self.server_port,
             'serverUsername': self.server_username,
-            'serverPassword': self.server_password,
-            'serverToken': self.server_token,
+            'config_group': self.configuration.config_group,
             'iopsLimit': None,
             'bandwidthLimit': None,
         }

doc/source/configuration/block-storage/drivers/dell-emc-scaleio-driver.rst

@@ -273,6 +273,33 @@ parameters as follows:
    san_password = SIO_PASSWD
    san_thin_provision = false
 
+Connector configuration
+~~~~~~~~~~~~~~~~~~~~~~~
+
+Before using attach/detach volume operations VxFlex OS connector must be
+properly configured. On each node where VxFlex OS SDC is installed do the
+following:
+
+#. Create ``/opt/emc/scaleio/openstack/connector.conf`` if it does not
+   exist.
+
+   .. code-block:: console
+
+     $ mkdir -p /opt/emc/scaleio/openstack
+     $ touch /opt/emc/scaleio/openstack/connector.conf
+
+#. For each VxFlex OS section in the ``cinder.conf`` create the same section in
+   the ``/opt/emc/scaleio/openstack/connector.conf`` and populate it with
+   passwords. Example:
+
+   .. code-block:: ini
+
+      [vxflexos]
+      san_password = SIO_PASSWD
+
+      [vxflexos-new]
+      san_password = SIO2_PASSWD
+
 Configuration options
 ~~~~~~~~~~~~~~~~~~~~~