deploy: add configmap for ceph.conf

added an example configmap for the
ceph.conf file. This allows the users to
specify different ceph configuration when
deploying cephcsi.

Signed-off-by: Madhu Rajanna <madhupr007@gmail.com>

examples/ceph-conf.yaml

@@ -0,0 +1,28 @@
+---
+# This is a sample configmap that helps define a Ceph configuration as required
+# by the CSI plugins.
+
+# Sample ceph.conf available at
+# https://github.com/ceph/ceph/blob/master/src/sample.ceph.conf Detailed
+# documentation is available at
+# https://docs.ceph.com/en/latest/rados/configuration/ceph-conf/
+apiVersion: v1
+kind: ConfigMap
+data:
+  ceph.conf: |
+    [global]
+    auth_cluster_required = cephx
+    auth_service_required = cephx
+    auth_client_required = cephx
+
+    # Workaround for http://tracker.ceph.com/issues/23446
+    fuse_set_user_groups = false
+
+    # ceph-fuse which uses libfuse2 by default has write buffer size of 2KiB
+    # adding 'fuse_big_writes = true' option by default to override this limit
+    # see https://github.com/ceph/ceph-csi/issues/1928
+    fuse_big_writes = true
+  # keyring is a required key and its value should be empty
+  keyring: |
+metadata:
+  name: ceph-config