Merge branch 'stmmac-dma-ops-multiqueue'

Joao Pinto says:

====================
net: stmmac: prepare dma operations for multiple queues

As agreed with David Miller, this patch-set is the second of 3 to enable
multiple queues in stmmac.

This second one concentrates on dma operations adding functionalities as:
a) DMA Operation Mode configuration per channel and done in the multiple
queues configuration function
b) DMA IRQ enable and Disable by channel
c) DMA start and stop by channel
d) RX and TX ring length configuration by channel
e) RX and TX set tail pointer by channel
f) DMA Channel initialization broke into Channel comon, RX and TX
initialization
g) TSO being configured for all available channels
h) DMA interrupt treatment by channel
====================

Signed-off-by: David S. Miller <davem@davemloft.net>