Merge branch 'net-dsa-qca8k-check-return-value-of-read-functions-correctly'

Yang Yingliang says:

====================
net: dsa: qca8k: check return value of read functions correctly

patch #1 - Change return type and add output parameter to make check
return value of read  functions correctly.

patch #2 - Add missing check return value in qca8k_phylink_mac_config().
====================

Link: https://lore.kernel.org/r/20210529030439.1723306-1-yangyingliang@huawei.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>