KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command

KVM: SVM: Add KVM_SEV_RECEIVE_UPDATE_DATA command

The command is used for copying the incoming buffer into the
SEV guest memory space.

Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Paolo Bonzini <[email protected]>
Cc: Joerg Roedel <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Tom Lendacky <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Reviewed-by: Steve Rutherford <[email protected]>
Signed-off-by: Brijesh Singh <[email protected]>
Signed-off-by: Ashish Kalra <[email protected]>
Message-Id: <c5d0e3e719db7bb37ea85d79ed4db52e9da06257.1618498113[email protected]>
Signed-off-by: Paolo Bonzini <[email protected]>