vmm: config: Move TDX to rely on PayloadConfig

Removing the option --tdx to specify that we want to run a TD VM. Rely
on --platform option by adding the "tdx" boolean parameter. This is the
new way for enabling TDX with Cloud Hypervisor.

Along with this change, the way to retrieve the firmware path has been
updated to rely on the recently introduced PayloadConfig structure.

Fixes #4556

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>

vmm/src/lib.rs

@@ -1419,8 +1419,6 @@ impl Vmm {
         let vm_config = vm.get_config();
         #[cfg(all(feature = "kvm", target_arch = "x86_64"))]
         let common_cpuid = {
-            #[cfg(feature = "tdx")]
-            let tdx_enabled = vm_config.lock().unwrap().tdx.is_some();
             let phys_bits = vm::physical_bits(vm_config.lock().unwrap().cpus.max_phys_bits);
             arch::generate_common_cpuid(
                 hypervisor,
@@ -1429,7 +1427,7 @@ impl Vmm {
                 phys_bits,
                 vm_config.lock().unwrap().cpus.kvm_hyperv,
                 #[cfg(feature = "tdx")]
-                tdx_enabled,
+                vm_config.lock().unwrap().is_tdx_enabled(),
             )
             .map_err(|e| {
                 MigratableError::MigrateReceive(anyhow!("Error generating common cpuid': {:?}", e))
@@ -1612,8 +1610,6 @@ impl Vmm {
         let dest_cpuid = &{
             let vm_config = &src_vm_config.lock().unwrap();
 
-            #[cfg(feature = "tdx")]
-            let tdx_enabled = vm_config.tdx.is_some();
             let phys_bits = vm::physical_bits(vm_config.cpus.max_phys_bits);
             arch::generate_common_cpuid(
                 self.hypervisor.clone(),
@@ -1622,7 +1618,7 @@ impl Vmm {
                 phys_bits,
                 vm_config.cpus.kvm_hyperv,
                 #[cfg(feature = "tdx")]
-                tdx_enabled,
+                vm_config.is_tdx_enabled(),
             )
             .map_err(|e| {
                 MigratableError::MigrateReceive(anyhow!("Error generating common cpuid: {:?}", e))
@@ -2053,8 +2049,6 @@ mod unit_tests {
             sgx_epc: None,
             numa: None,
             watchdog: false,
-            #[cfg(feature = "tdx")]
-            tdx: None,
             #[cfg(feature = "gdb")]
             gdb: false,
             platform: None,