ASoC: wm8940: Correct typo in control name

[ Upstream commit b4799520dcd6fe1e14495cecbbe9975d847cd482 ]

Fixes: 0b5e92c5 ("ASoC WM8940 Driver")
Reported-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Tested-by: Ankur Tyagi <ankur.tyagi85@gmail.com>
Link: https://patch.msgid.link/20250821082639.1301453-3-ckeepax@opensource.cirrus.com


Signed-off-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>