add storage serialization methods for privateuse1 (#98920)
add entry for privateuse1 storage serialization register_package in _register_device_module.
1. User only need to implement `privateuse1_tag` and `privateuse1_deserialize` in the device module of open device. When registering device module, the methods are registered with _package_registry in storage serialization.
2. Provides a fixed sequence number 30 for privateuse1 in storage serialization _package_registry list.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/98920
Approved by: https://github.com/ezyang
