net: stmmac: Add GFP_DMA32 for rx buffers if no 64 capability

Use page_pool_alloc_pages instead of page_pool_dev_alloc_pages, which
can give the gfp parameter, in the case of not supporting 64-bit width,
using 32-bit address memory can reduce a copy from swiotlb.

Signed-off-by: David Wu <david.wu@rock-chips.com>
Signed-off-by: David S. Miller <davem@davemloft.net>