sunxi: backport increased SATA/AHCI DMA TX/RX FIFOs

sunxi: backport increased SATA/AHCI DMA TX/RX FIFOs

This backports SATA performance boost from 5.3 kernel:

 Increasing the SATA/AHCI DMA TX/RX FIFOs (P0DMACR.TXTS and .RXTS, ie.
 TX_TRANSACTION_SIZE and RX_TRANSACTION_SIZE) from default 0x0 each to
 0x3 each, gives a write performance boost of 120 MiB/s to 132 MiB/s from
 lame 36 MiB/s to 45 MiB/s previously.  Read performance is above 200
 MiB/s. [tested on SSD using dd bs=4K/8K/12K/16K/20K/24K/32K: peak-perf
 at 12K]

 dd bs  Before MB/s  After MB/s  Increase
 4k            14.4        16.5       15%
 64k           34.5        74.4      116%
 1M            40.5        93.2      130%

Ref: https://forum.openwrt.org/t/sunxi-sata-write-speed-patch/54555/5
Signed-off-by: Aleksander Jan Bajkowski <A.Bajkowski@stud.elka.pw.edu.pl>
[commit subject & description tweaks]
Signed-off-by: Petr Štetiar <ynezz@true.cz>