docs: update README.md with Linux namespace adjustment.

Signed-off-by: Krisztian Litkey <krisztian.litkey@intel.com>

Author: klihub

README.md

@@ -254,6 +254,7 @@ container parameters:
       - Block I/O class
       - RDT class
       - Linux seccomp policy
+    - Linux namespaces
 
 ### Container Updates
 
@@ -349,11 +350,14 @@ for rejecting adjustment of the seccomp policy profile based on the type of poli
 profile set for the container. These types include the runtime default seccomp
 policy profile, a custom policy profile, and unconfined security profiles.
 
-3. Verify global mandatory plugins: Verify that all configured mandatory
+3. Reject Linux Namespace adjustment: Reject any adjustment which tries to
+alter Linux namespaces of a container.
+
+4. Verify global mandatory plugins: Verify that all configured mandatory
 plugins are present and have processed a container. Otherwise reject the
 creation of the container.
 
-4. Verify annotated mandatory plugins: Verify that an annotated set of
+5. Verify annotated mandatory plugins: Verify that an annotated set of
 container-specific mandatory plugins are present and have processed a
 container. Otherwise reject the creation of the container.
 
@@ -362,11 +366,11 @@ allows one to deploy mandatory plugins as containers themselves.
 
 #### Default Validation Scope
 
-Currently only OCI hook injection and Linux seccomp policy can be restricted
-using the default validator. However, this probably will change in the future.
-Especially when NRI is extended with control over more container parameters.
-If newly added controls will have security implications, expect corresponding
-configurable restrictions in the default validator.
+Currently only OCI hook injection, Linux seccomp policy and Linux namespace
+adjustment can be restricted using the default validator. However, this probably
+will change in the future. Especially when NRI is extended with control over more
+container parameters. If newly added controls will have security implications,
+expect corresponding configurable restrictions in the default validator.
 
 ## Runtime Adaptation