KVM: SVM: Ensure PSP module is initialized if KVM module is built-in

KVM: SVM: Ensure PSP module is initialized if KVM module is built-in

The kernel's initcall infrastructure lacks the ability to express
dependencies between initcalls, whereas the modules infrastructure
automatically handles dependencies via symbol loading.  Ensure the
PSP SEV driver is initialized before proceeding in sev_hardware_setup()
if KVM is built-in as the dependency isn't handled by the initcall
infrastructure.

Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Ashish Kalra <ashish.kalra@amd.com>
Link: https://lore.kernel.org/r/f78ddb64087df27e7bcb1ae0ab53f55aa0804fab.1739226950.git.ashish.kalra@amd.com
Signed-off-by: Sean Christopherson <seanjc@google.com>