brcmfmac: set F2 SDIO block size to 128 bytes for BCM4329

Setting F2 block size to 128 bytes for BCM4329 allows to significantly
improve RX throughput on NVIDIA Tegra20. Before this change the throughput
was capped to 30 Mbit/s on Tegra, now throughput is at 40 Mbit/s, which is
a maximum throughput for the BCM4329 chip. The F2 block size is borrowed
from the downstream BCMDHD driver. The comment in the BCMDHD driver says
that 128B improves throughput and turns out that it works for the brcmfmac
as well.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200830191439.10017-4-digetx@gmail.com