net: mdio: ipq8064: add regmap config to disable REGCACHE

stable inclusion
from stable-5.10.51
commit b5713dac19168234029efa281b46266417ab51ec
bugzilla: 175263 https://gitee.com/openeuler/kernel/issues/I4DT6F

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=b5713dac19168234029efa281b46266417ab51ec



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[ Upstream commit b097bea1 ]

mdio drivers should not use REGCHACHE. Also disable locking since it's
handled by the mdio users and regmap is always accessed atomically.

Signed-off-by: Ansuel Smith <ansuelsmth@gmail.com>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Acked-by: Weilong Chen <chenweilong@huawei.com>
Signed-off-by: Chen Jun <chenjun102@huawei.com>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>