dmaengine: sun6i: Do not use virt_to_phys

This breaks on RISC-V, because dma_pool_alloc returns addresses which
are not in the linear map. Instead, plumb through the physical address
which is already known anyway.

Acked-by: Maxime Ripard <maxime@cerno.tech>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Link: https://lore.kernel.org/r/20220424172759.33383-3-samuel@sholland.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>