amd-xgbe: Fix DMA API debug warning

When running a kernel configured with CONFIG_DMA_API_DEBUG=y a warning
is issued:
  DMA-API: device driver tries to sync DMA memory it has not allocated

This warning is the result of mapping the full range of the Rx buffer
pages allocated and then performing a dma_sync_single_for_cpu against
a calculated DMA address. The proper thing to do is to use the
dma_sync_single_range_for_cpu with a base DMA address and an offset.

Reported-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Tested-by: Kim Phillips <kim.phillips@arm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>