ALSA: virtuoso: fix WM8766 register writes with MSB

The check for the volume update latch bit was accidentally in the wrong
function, where it would prevent the MSB from being written, instead of
correctly ignoring it for cached values.

Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>