[Build System] Move host lipo step after install step

(cherry picked from commit c123f42)

utils/build-script

@@ -918,6 +918,9 @@ class BuildScriptInvocation(object):
         for host_target in all_hosts:
             for product_class in impl_product_classes:
                 self._execute_install_action(host_target, product_class)
+
+        # Lipo...
+        self._execute_merged_host_lipo_action()
 
         # Non-build-script-impl products...
         # Note: currently only supports building for the host.
@@ -957,9 +960,6 @@ class BuildScriptInvocation(object):
         for host_target in all_hosts:
             self._execute_package_action(host_target)
 
-        # Lipo...
-        self._execute_merged_host_lipo_action()
-
     def _execute_build_action(self, host_target, product_class):
         action_name = "{}-{}-build".format(host_target.name,
                                            product_class.product_name())