doc: cosmetic: fwu_updates: Fix formatting

Remove one of the double colon so ..code-block is used for formatting.

Signed-off-by: Leonard Anderweit <l.anderweit@phytec.de>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>

doc/develop/uefi/fwu_updates.rst

@@ -170,7 +170,7 @@ build the tool, enable::
 
     CONFIG_TOOLS_MKEFICAPSULE=y
 
-Run the following commands to generate the accept/revert capsules::
+Run the following commands to generate the accept/revert capsules:
 
 .. code-block:: bash
 
@@ -180,7 +180,7 @@ Run the following commands to generate the accept/revert capsules::
       <capsule_file_name>
 
 Some examples of using the mkeficapsule tool for generation of the
-empty capsule would be::
+empty capsule would be:
 
 .. code-block:: bash