Migrate the existing code to use the new LAN9118 MMIO wrappers, ensuring that timing requirements are respected. The newly redundant stalls will be removed in a subsequent patch. Cc: Leif Lindholm <leif.lindholm@linaro.org> Cc: Ryan Harkin <ryan.harkin@linaro.org> Signed-off-by: Mark Rutland <mark.rutland@arm.com> Contributed-under: TianoCore Contribution Agreement 1.0 Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>