Building grunt images fails with the following link errors.

/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:6287: undefined reference to `sev_issue_cmd_external_user'
arch/x86/kvm/svm.o: In function `sev_launch_secret':
/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:6863: undefined reference to `psp_copy_user_blob'
/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:6872: undefined reference to `psp_copy_user_blob'
arch/x86/kvm/svm.o: In function `sev_unbind_asid':
/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:1747: undefined reference to `sev_guest_deactivate'
/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:1750: undefined reference to `sev_guest_df_flush'
/mnt/host/source/src/third_party/kernel/next/arch/x86/kvm/svm.c:1759: undefined reference to `sev_guest_decommission'
make[1]: *** [/mnt/host/source/src/third_party/kernel/next/Makefile:1059: vmlinux] Error 1

Analysis suggests missing dependencies in the upstream kernel.