syms: Add 'global:' keyword to LIBVIRT_5.8 section

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

src/libvirt_public.syms

@@ -858,6 +858,7 @@ LIBVIRT_5.7.0 {
 } LIBVIRT_5.6.0;
 
 LIBVIRT_5.8.0 {
+    global:
         virConnectSetIdentity;
 } LIBVIRT_5.7.0;