Documentation: virt: Fix up pre-formatted text block for SEV ioctls

A missing newline after "::" resulted in the htmldocs build failing to
recognize the start of a pre-formatted block of text, resulting in

  kernel/linux/Documentation/virt/coco/sev-guest.rst:75: WARNING: Inline emphasis start-string without end-string.
  kernel/linux/Documentation/virt/coco/sev-guest.rst:78: WARNING: Inline emphasis start-string without end-string.
  kernel/linux/Documentation/virt/coco/sev-guest.rst:81: WARNING: Inline emphasis start-string without end-string.
  kernel/linux/Documentation/virt/coco/sev-guest.rst:83: WARNING: Definition list ends without a blank line; unexpected unindent.

Fix it.

Fixes: f5db884 ("crypto: ccp: Add the SNP_PLATFORM_STATUS command")
Closes: https://lore.kernel.org/linux-next/[email protected]/
Reported-by: Stephen Rothwell <[email protected]>
Signed-off-by: Michael Roth <[email protected]>
Signed-off-by: Borislav Petkov (AMD) <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: mdroth

Documentation/virt/coco/sev-guest.rst

@@ -71,6 +71,7 @@ The host ioctls are issued to a file descriptor of the /dev/sev device.
 The ioctl accepts the command ID/input structure documented below.
 
 ::
+
         struct sev_issue_cmd {
                 /* Command ID */
                 __u32 cmd;