tools: add 'domlaunchsecinfo' virsh command

This command reports the launch security parameters for
a guest, allowing an external tool to perform a launch
attestation.

Reviewed-by: Peter Krempa <pkrempa@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>

docs/manpages/virsh.rst

@@ -2057,6 +2057,23 @@ destination hosts have synchronized time (i.e., NTP daemon is running
 on both of them).
 
 
+domlaunchsecinfo
+----------------
+
+**Syntax:**
+
+::
+
+   domlaunchsecinfo domain
+
+Returns information about the launch security parameters associated
+with a running domain.
+
+The set of parameters reported will vary depending on which type of
+launch security protection is active. If none is active, no parameters
+will be reported.
+
+
 dommemstat
 ----------