KVM: SEV: Wire up kvm_x86_ops.gmem_xxx() if and only if CONFIG_KVM_AMD_SEV=y

Wire up the SEV-SNP guest_memfd kvm_x86_ops hooks if and only if SEV is
actually enabled, and drop the now-unnecessary stubs.  Leaving the hooks
NULL allows the static call infrastructure to elide the CALL+RET, and more
importantly, referencing the hooks if and only if SEV support is enabled
will allow conditionally definining the hooks using their corresponding
HAVE_KVM_ARCH_GMEM_XXX Kconfig.

No functional change intended.

Cc: stable@vger.kernel.org # 6.12.x
Reviewed-by: Ackerley Tng <ackerleytng@google.com>
Link: https://patch.msgid.link/20260709204948.1988414-5-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

0 files changed, 0 insertions, 0 deletions