crypto: ccp: Add Platform Security Processor (PSP) device support
The Platform Security Processor (PSP) is part of the AMD Secure
Processor (AMD-SP) functionality. The PSP is a dedicated processor
that provides support for key management commands in Secure Encrypted
Virtualization (SEV) mode, along with software-based Trusted Execution
Environment (TEE) to enable third-party trusted applications.
Note that the key management functionality provided by the SEV firmware
can be used outside of the kvm-amd driver hence it doesn't need to
depend on CONFIG_KVM_AMD.