MdeModulePkg: introduce helper library to register non-discoverable devices

MdeModulePkg: introduce helper library to register non-discoverable devices

Non-discoverable devices need to be registered explicitly by the platform.
Introduce a helper library that takes care of this.

This implementation currently only supports registering devices that are
covered by one or more MMIO resources. The underlying protocol allows for
more flexibility than that, but this is currently sufficient for the use
cases that we know about.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Tested-by: Marcin Wojtas <mw@semihalf.com>