savevm: split save_live_setup from save_live_state

This patch splits stage 1 to its own function for both save_live
users, ram and block.  It is just a copy of the function, removing the
parts of the other stages.  Optimizations would came later.

Signed-off-by: Juan Quintela <quintela@redhat.com>
diff --git a/savevm.c b/savevm.c
index afa0c9e..0b80a94 100644
--- a/savevm.c
+++ b/savevm.c
@@ -1573,7 +1573,7 @@
     QTAILQ_FOREACH(se, &savevm_handlers, entry) {
         int len;
 
-        if (!se->ops || !se->ops->save_live_state) {
+        if (!se->ops || !se->ops->save_live_setup) {
             continue;
         }
         if (se->ops && se->ops->is_active) {
@@ -1593,7 +1593,7 @@
         qemu_put_be32(f, se->instance_id);
         qemu_put_be32(f, se->version_id);
 
-        ret = se->ops->save_live_state(f, QEMU_VM_SECTION_START, se->opaque);
+        ret = se->ops->save_live_setup(f, se->opaque);
         if (ret < 0) {
             qemu_savevm_state_cancel(f);
             return ret;