REF:https://github.com/tianocore/edk2/issues/10529
Adds a new PEI library instance for RngLib that uses the RNG services
provided by the RNG PPI.
This library instance will add a DEPEX on gEfiRngPpiGuid on modules
it links against. It can be used to allow PEIMs to get RNG support
over a dynamic interface.
Signed-off-by: Michael Kubacki <michael.kubacki@microsoft.com>