tests/vm: Let kvm_available() work in cross environments

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Message-Id: <20181013004034.6968-7-f4bug@amsat.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Fam Zheng <famz@redhat.com>

scripts/qemu.py

@@ -27,6 +27,8 @@ LOG = logging.getLogger(__name__)
 
 
 def kvm_available(target_arch=None):
+    if target_arch and target_arch != os.uname()[4]:
+        return False
     return os.access("/dev/kvm", os.R_OK | os.W_OK)