docs/admin-guide/cgroup-v2: fix mount opt rendering

Due to an extra empty line between the option and its description
it is rendered not like in other places.

Remove the empty lines to fix.
Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20210120001824.385168-11-kolyshkin@gmail.comSigned-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/admin-guide/cgroup-v2.rst

@@ -174,7 +174,6 @@ disabling controllers in v1 and make them always available in v2.
 cgroup v2 currently supports the following mount options.
 
   nsdelegate
-
 	Consider cgroup namespaces as delegation boundaries.  This
 	option is system wide and can only be set on mount or modified
 	through remount from the init namespace.  The mount option is
@@ -182,7 +181,6 @@ cgroup v2 currently supports the following mount options.
 	Delegation section for details.
 
   memory_localevents
-
         Only populate memory.events with data for the current cgroup,
         and not any subtrees. This is legacy behaviour, the default
         behaviour without this option is to include subtree counts.
@@ -191,7 +189,6 @@ cgroup v2 currently supports the following mount options.
         option is ignored on non-init namespace mounts.
 
   memory_recursiveprot
-
         Recursively apply memory.min and memory.low protection to
         entire subtrees, without requiring explicit downward
         propagation into leaf cgroups.  This allows protecting entire