KVM: x86: prefer "depends on" to "select" for SEV

Avoid reverse dependencies.  Instead, SEV will only be enabled if
the PSP driver is available.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>

arch/x86/kvm/Kconfig

@@ -85,9 +85,7 @@ config KVM_AMD_SEV
 	def_bool y
 	bool "AMD Secure Encrypted Virtualization (SEV) support"
 	depends on KVM_AMD && X86_64
-	select CRYPTO_DEV_CCP
-	select CRYPTO_DEV_CCP_DD
-	select CRYPTO_DEV_SP_PSP
+	depends on CRYPTO_DEV_CCP && CRYPTO_DEV_CCP_DD && CRYPTO_DEV_SP_PSP
 	---help---
 	Provides support for launching Encrypted VMs on AMD processors.