ASoC: codecs: Remove unused rt566[58]_sel_asrc_clk_src

rt5665_sel_asrc_clk_src() was added in 2016 by
commit 33ada14a ("ASoC: add rt5665 codec driver")

rt5668_sel_asrc_clk_src() was added in 2018 by
commit d59fb285 ("ASoC: rt5668: add rt5668B codec driver")

Neither have been used.

Remove them.

Signed-off-by: "Dr. David Alan Gilbert" <linux@treblig.org>
Link: https://patch.msgid.link/20250420232733.182802-1-linux@treblig.org


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