Replace the halt loop in handle_vc_boot_ghcb() with an
sev_es_terminate(). The HLT gives the system no indication the guest is
unhappy. The termination request will signal there was an error during
VC handling during boot.

  [ bp: Update it to pass the reason set too. ]
Signed-off-by: Peter Gonda <pgonda@google.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Joerg Roedel <jroedel@suse.de>
Link: https://lore.kernel.org/r/20220317211913.1397427-1-pgonda@google.com