firmware: turris-mox-rwtm: fix reply status decoding function

stable inclusion
from stable-5.10.52
commit 271c12dbeb62e53b10d45fe904b3dc7afb779aae
bugzilla: 175542 https://gitee.com/openeuler/kernel/issues/I4DTKU

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=271c12dbeb62e53b10d45fe904b3dc7afb779aae



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[ Upstream commit e34e6025 ]

The status decoding function mox_get_status() currently contains an
incorrect check: if the error status is not MBOX_STS_SUCCESS, it always
returns -EIO, so the comparison to MBOX_STS_FAIL is never executed and
we don't get the actual error code sent by the firmware.

Fix this.

Signed-off-by: Marek Behún <kabel@kernel.org>
Reviewed-by: Pali Rohár <pali@kernel.org>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Fixes: 389711b3 ("firmware: Add Turris Mox rWTM firmware driver")
Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
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>