ASoC: rt5665: Fix a typo in the name of a function

All function names start with rt5665_, except 'rt5655_set_verf()'.
It is likely a typo.

Fix it to be consistent.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Link: https://lore.kernel.org/r/20190722212639.26954-1-christophe.jaillet@wanadoo.fr


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