ASoC: pxa: remove duplicated CONFIG_SND_PXA2XX_AC97 entry

'config SND_PXA2XX_AC97' is already present in sound/arm/Kconfig with
a prompt.

Commit 734c2d4b ("[ALSA] ASoC pxa2xx build support") redundantly
added the second one to sound/soc/pxa/Kconfig.

Remove it.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Link: https://lore.kernel.org/r/20240204091424.38306-1-masahiroy@kernel.org


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