vmm: Introduce kernel hashes measured boot

This introduces the kernel hashes measured boot table into
cloud hypervisor if a cmdline and kernel is passed into an
SEV-SNP CVM, incorporating a kernel/cmdline/optional initrd
into a memory page that is measured into the launch digest
of a SEV-SNP CVM. If both --kernel and --cmdline are not
provided, we do not insert this data page

Signed-off-by: Kevin Hui <kevinhui@meta.com>

vmm/src/lib.rs

@@ -91,6 +91,13 @@ pub mod migration_transport;
 mod pci_segment;
 pub mod seccomp_filters;
 mod serial_manager;
+#[cfg(all(
+    feature = "kvm",
+    feature = "sev_snp",
+    feature = "fw_cfg",
+    target_arch = "x86_64"
+))]
+pub(crate) mod sev;
 mod sigwinch_listener;
 mod sync_utils;
 mod uffd;