cloud-ifupdown-helper patch and reattach-vf.sh script are rendered in
htmldocs output as normal paragraphs instead of literal code blocks
due to missing separator from respective code block marker. Add it.

Fixes: 738baea4970b ("Documentation: networking: net_failover: Fix documentation")
Signed-off-by: Bagas Sanjaya <redacted>
---
 Documentation/networking/net_failover.rst | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Documentation/networking/net_failover.rst b/Documentation/networking/net_failover.rst
index f4e1b4e07adc8d..51de30597fbe40 100644
--- a/Documentation/networking/net_failover.rst
+++ b/Documentation/networking/net_failover.rst

@@ -99,6 +99,7 @@ Below is the patch snippet used with 'cloud-ifupdown-helper' script found on
 Debian cloud images:
 
 ::
+
   @@ -27,6 +27,8 @@ do_setup() {
        local working="$cfgdir/.$INTERFACE"
        local final="$cfgdir/$INTERFACE"