EVM: ensure trusted and encypted key symbols are available to EVM

Select trusted and encrypted keys if EVM is selected, to ensure
the requisite symbols are available.  Otherwise, these can be
selected as modules while EVM is static, leading to a kernel
build failure.
Signed-off-by: James Morris <jmorris@namei.org>

security/integrity/evm/Kconfig

 config EVM
 	boolean "EVM support"
-	depends on SECURITY && KEYS && ENCRYPTED_KEYS
+	depends on SECURITY && KEYS
 	select CRYPTO_HMAC
 	select CRYPTO_MD5
 	select CRYPTO_SHA1
+	select ENCRYPTED_KEYS
+	select TRUSTED_KEYS
 	default n
 	help
 	  EVM protects a file's security extended attributes against