tests: validate CPU count in the test infra

Instead of validating number of CPU in the test case itself,
moving the checking of the CPU count to Guest struct with a
new function as The Guest already has the Default CPU number.

Signed-off-by: Muminul Islam <muislam@microsoft.com>

cloud-hypervisor/tests/integration.rs

@@ -2559,7 +2559,7 @@ fn _test_simple_launch(guest: &Guest) {
     let r = std::panic::catch_unwind(|| {
         guest.wait_vm_boot().unwrap();
 
-        assert_eq!(guest.get_cpu_count().unwrap_or_default(), 1);
+        guest.validate_cpu_count(None);
         assert!(guest.get_total_memory().unwrap_or_default() > 480_000);
         assert_eq!(guest.get_pci_bridge_class().unwrap_or_default(), "0x060000");
         assert!(check_sequential_events(

test_infra/src/lib.rs

@@ -1385,6 +1385,14 @@ impl Guest {
             if self.nested { "" } else { ",nested=off" }
         )
     }
+
+    pub fn validate_cpu_count(&self, expected_cpu_count: Option<u32>) {
+        let cpu = match expected_cpu_count {
+            Some(count) => count,
+            None => self.num_cpu,
+        };
+        assert_eq!(self.get_cpu_count().unwrap_or_default(), cpu);
+    }
 }
 
 #[derive(Default)]