Remove reference to removed item

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/docs/3.0-migration-guide.md b/docs/3.0-migration-guide.md
index d66cb7f..17fe956 100644
--- a/docs/3.0-migration-guide.md
+++ b/docs/3.0-migration-guide.md
@@ -916,13 +916,6 @@
 - `MBEDTLS_ERR_SSL_BAD_HS_XXX`
 
 Migration paths:
-- `MBEDTLS_ERR_SSL_CERTIFICATE_REQUIRED` and `MBEDTLS_ERR_SSL_INVALID_VERIFY_HASH`
-  should never be returned from Mbed TLS, and there is no need to check for it.
-
-  Users should simply remove manual checks for those codes, and let the Mbed TLS
-  team know if — contrary to the team's understanding — there is in fact a situation
-  where one of them was ever returned.
-
 - `MBEDTLS_ERR_SSL_CERTIFICATE_TOO_LARGE` has been removed, and
   `MBEDTLS_ERR_SSL_BUFFER_TOO_SMALL` is returned instead if the user's own certificate
   is too large to fit into the output buffers.