net: ena: use lower_32_bits()/upper_32_bits() to split dma address

In ena_com_mem_addr_set(), use the above functions to split dma address
to the lower 32 bits and the higher 16 bits.

Signed-off-by: Netanel Belgazal <netanel@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>