iio: dac: ad5446: Fix read_raw not returning set value

stable inclusion
from stable-v5.10.114
commit 1060604fc7f2e0fdf083e13c2d0a471e95342c90
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I5IY1V

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=1060604fc7f2e0fdf083e13c2d0a471e95342c90



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commit 89a01cd6 upstream.

read_raw should return the un-scaled value.

Fixes: 5e06bdfb ("staging:iio:dac:ad5446: Return cached value for 'raw' attribute")
Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220406105620.1171340-1-michael.hennerich@analog.com


Cc: <Stable@vger.kernel.org>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>
Acked-by: Xie XiuQi <xiexiuqi@huawei.com>