ASoC: rt712-sdca: remove redundant else path of if statement

ASoC: rt712-sdca: remove redundant else path of if statement

There is an if/else check where the else part is executed if
adc_vol_flag is true, this else path checks if adc_vol_flag
is true (which is a redundant second check) and the if path is
always taken. Remove the redundant check and remove the else
path since that can never occur.

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://patch.msgid.link/20250507140907.255562-1-colin.i.king@gmail.com
Signed-off-by: Mark Brown <broonie@kernel.org>