This is to remove invalid key "userSecretName" for
cephfs storageclass as we are having toruble to provision
a pvc with cephfs storageclass with "userSecretName" key .
Failed to provision volume with StorageClass
"cephfs": invalid option "userSecretName"
Change-Id: Ide52987c9f8ef8fc2327bf30747395e70dc05f99
53bdbf00ed