Documentation: net/mlx5: Add blank line separator before numbered lists

The doc forgets to add separator before numbered lists, which causes the
lists to be appended to previous paragraph inline instead.

Add the missing separator.

Fixes: f2d51e57 ("net/mlx5: Separate mlx5 driver documentation into multiple pages")
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: Bagas Sanjaya <bagasdotme@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>

Documentation/networking/device_drivers/ethernet/mellanox/mlx5/devlink.rst

@@ -40,6 +40,7 @@ flow_steering_mode: Device flow steering mode
 ---------------------------------------------
 The flow steering mode parameter controls the flow steering mode of the driver.
 Two modes are supported:
+
 1. 'dmfs' - Device managed flow steering.
 2. 'smfs' - Software/Driver managed flow steering.
 
@@ -99,6 +100,7 @@ between representors and stacked devices.
 By default metadata is enabled on the supported devices in E-switch.
 Metadata is applicable only for E-switch in switchdev mode and
 users may disable it when NONE of the below use cases will be in use:
+
 1. HCA is in Dual/multi-port RoCE mode.
 2. VF/SF representor bonding (Usually used for Live migration)
 3. Stacked devices