When a control changes value the return value from _put() should be 1 so
we get events generated to userspace notifying applications of the change.
While the I2S mux gets this right the S/PDIF mux does not, fix the return
value.

Fixes: c8609f38 ("ASoC: meson: add g12a tohdmitx control")
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20240103-meson-enum-val-v1-4-424af7a8fb91@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>