If CONFIG_REGMAP_SLIMBUS is not set,
make ARCH=x86_64 CROSS_COMPILE=x86_64-linux-gnu-,
will be failed, like this:

sound/soc/codecs/wcd934x.o: In function `wcd934x_codec_probe':
wcd934x.c:(.text+0x3310): undefined reference to `__regmap_init_slimbus'
make: *** [vmlinux] Error 1

Add select REGMAP_SLIMBUS to config SND_SOC_WCD934X.

Fixes: a61f3b4f ("ASoC: wcd934x: add support to wcd9340/wcd9341 codec")
Signed-off-by: Ren Zhijie <renzhijie2@huawei.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Link: https://lore.kernel.org/r/20220926074042.13297-1-renzhijie2@huawei.comSigned-off-by: Mark Brown <broonie@kernel.org>