MdeModulePkg DxeS3BootScriptLib: Add DESTRUCTOR S3BootScriptLibDeinitialize

MdeModulePkg DxeS3BootScriptLib: Add DESTRUCTOR S3BootScriptLibDeinitialize

PiDxeS3BootScriptLib has a constructor S3BootScriptLibInitialize() that
registers ready-to-lock callback S3BootScriptSmmEventCallBack() and several
more. The library is linked to SMM modules. If the module entry-point
function returns error (because of lack of resources, unsupported,
whatever), the module will be unloaded and the notify callback pointers
will point to undefined memory. On ready-to-lock exception occurs when
calling S3BootScriptSmmEventCallBack(), and probably all the other
callbacks registered by the constructor would also cause exception.

This patch is to implement library Destructor to free the resources
allocated by S3BootScriptLibInitialize() and unregister callbacks.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>