ASoC: cros_ec_codec: fix kconfig dependency warning for SND_SOC_CROS_EC_CODEC

When SND_SOC_CROS_EC_CODEC is enabled and CRYPTO is disabled, it results
in the following Kbuild warning:

WARNING: unmet direct dependencies detected for CRYPTO_LIB_SHA256
  Depends on [n]: CRYPTO [=n]
  Selected by [y]:
  - SND_SOC_CROS_EC_CODEC [=y] && SOUND [=y] && !UML && SND [=y] && SND_SOC [=y] && CROS_EC [=y]

The reason is that SND_SOC_CROS_EC_CODEC selects CRYPTO_LIB_SHA256 without
depending on or selecting CRYPTO while CRYPTO_LIB_SHA256 is subordinate to
CRYPTO.

Honor the kconfig menu hierarchy to remove kconfig dependency warnings.

Fixes: 93fa0af4 ("ASoC: cros_ec_codec: switch to library API for SHA-256")
Signed-off-by: Necip Fazil Yildiran <fazilyildiran@gmail.com>
Link: https://lore.kernel.org/r/20200917141803.92889-1-fazilyildiran@gmail.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/codecs/Kconfig

@@ -542,6 +542,7 @@ config SND_SOC_CQ0093VC
 config SND_SOC_CROS_EC_CODEC
 	tristate "codec driver for ChromeOS EC"
 	depends on CROS_EC
+	select CRYPTO
 	select CRYPTO_LIB_SHA256
 	help
 	  If you say yes here you will get support for the