Fix the return value of cs42l52_set_fmt() when clock inversion is
not allowed and also remove the useless variable ret.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

[We had been assigning to ret but then ignoring the value we assgined
-- broonie]
Signed-off-by: NWei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: NMark Brown <broonie@opensource.wolfsonmicro.com>
Cc: stable@vger.kernel.org