Silicon/Qemu: Renumber Dynamic PCDs to leave a gap

It is useful to have the PCDs of same type to be numbered
close together and thus a gap should be left between PCDs of
different types.

Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>
Cc: Tanmay Jagdale <tanmay.jagdale@linaro.org>
Signed-off-by: Tomas Pilar <tomas@nuviateam.com>
Reviewed-by: Leif Lindholm <leif@nuviainc.com>