Correct DMA channel number selection on AR816x family of
controllers. For Gigabit Ethernet version of AR816x, AR813x/AR815x
except L1D controller, use vendor recommended ASPM parameters.
While here, increase alc_dma_burst array size.  Broken H/W can
return bogus value in theory.

Add Killer E2400 Gigabit Ethernet support.
It seems Killer E2200/E2400 has a BIOS misconfiguration or silicon
bug which triggers DMA write errors when driver uses advertised
maximum payload size.  Force the maximum payload size to 128 bytes
in DMA configuration.
This change should fix occasional DMA write errors reported on
Killer E2200.

Add a missing change in r304575.