Fix inconsistencies in Flexvolume docs (#9706)

* Fix inconsistencies in Flexvolume docs

* remove code highlighting for Flexvolume and CSI

content/en/docs/concepts/policy/pod-security-policy.md

@@ -35,7 +35,7 @@ administrator to control the following:
 | Usage of host networking and ports                  | [`hostNetwork`, `hostPorts`](#host-namespaces) |
 | Usage of volume types                               | [`volumes`](#volumes-and-file-systems)      |
 | Usage of the host filesystem                        | [`allowedHostPaths`](#volumes-and-file-systems) |
-| White list of FlexVolume drivers                    | [`allowedFlexVolumes`](#flexvolume-drivers) |
+| White list of Flexvolume drivers                    | [`allowedFlexVolumes`](#flexvolume-drivers) |
 | Allocating an FSGroup that owns the pod's volumes   | [`fsGroup`](#volumes-and-file-systems)      |
 | Requiring the use of a read only root file system   | [`readOnlyRootFilesystem`](#volumes-and-file-systems) |
 | The user and group IDs of the container             | [`runAsUser`, `supplementalGroups`](#users-and-groups) |
@@ -452,12 +452,12 @@ to effectively limit access to the specified `pathPrefix`.
 **ReadOnlyRootFilesystem** - Requires that containers must run with a read-only
 root filesystem (i.e. no writable layer).
 
-### FlexVolume drivers
+### Flexvolume drivers
 
-This specifies a whiltelist of flex volume drivers that are allowed to be used
-by flexVolume. An empty list or nil means there is no restriction on the drivers.
+This specifies a whiltelist of Flexvolume drivers that are allowed to be used
+by flexvolume. An empty list or nil means there is no restriction on the drivers.
 Please make sure [`volumes`](#volumes-and-file-systems) field  contains the
-`flexVolume` volume type, no FlexVolume driver is allowed otherwise.
+`flexVolume` volume type; no Flexvolume driver is allowed otherwise.
 
 For example: