Check wstatus in check_raw_capability.

The winfo field is only populated with capability bits if wstatus is
nonzero.  If wstatus is zero, those bits are re-used and indicate why
HAXM is not usable.

Bug: 357064526
Test: tested locally
Change-Id: I9cb0c82267095e4f89c879d48d8a3b7c00dfe36c
Reviewed-on: https://chromium-review.googlesource.com/c/crosvm/crosvm/+/5792562
Commit-Queue: Idan Raiter <idanr@google.com>
Commit-Queue: Judson Powers <judsonp@google.com>
Auto-Submit: Judson Powers <judsonp@google.com>
Reviewed-by: Idan Raiter <idanr@google.com>

hypervisor/src/haxm/vm.rs

@@ -122,6 +122,13 @@ impl HaxmVm {
             return false;
         }
 
+        // If wstatus is zero, HAXM is not usable.
+        // In this case, the winfo bits indicate why, rather than communicating capability
+        // information.
+        if capability_info.wstatus == 0 {
+            return false;
+        }
+
         (cap & capability_info.winfo as u32) != 0
     }