ubuntu-core-initramfs: copy missing modules.builtin.modinfo

This file is needed by dracut-install when installing modules. So we
should copy it.

bin/ubuntu-core-initramfs

@@ -344,7 +344,7 @@ def create_initrd(parser, args):
             add_modules_from_file(main, kernel_root, modules, firmware, module_load, db,
                                   warn_discoverable=True)
 
-        for modulesf in ["modules.order", "modules.builtin", "modules.builtin.bin"]:
+        for modulesf in ["modules.order", "modules.builtin", "modules.builtin.bin", "modules.builtin.modinfo"]:
             subprocess.check_call(
                 [
                     "/usr/lib/dracut/dracut-install",