[PATCH-for-8.0] tests/vm: Update get_default_jobs() to work on non-x86_64 non-KVM hosts

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On non-x86_64 host, if KVM is not available we get:

  Traceback (most recent call last):
    File "tests/vm/basevm.py", line 634, in main
      vm = vmcls(args, config=config)
    File "tests/vm/basevm.py", line 104, in __init__
      mem = max(4, args.jobs)
  TypeError: '>' not supported between instances of 'NoneType' and 'int'

Fix by always returning a -- not ideal but safe -- '1' value.

Fixes: b09539444a ("tests/vm: allow us to take advantage of MTTCG")
Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
---
 tests/vm/basevm.py | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
index 2276364c42..23229e23d1 100644
--- a/tests/vm/basevm.py
+++ b/tests/vm/basevm.py
@@ -569,8 +569,7 @@ def get_default_jobs():
                 # more cores. but only up to a reasonable limit. User
                 # can always override these limits with --jobs.
                 return min(multiprocessing.cpu_count() // 2, 8)
-        else:
-            return 1
+        return 1
 
     parser = argparse.ArgumentParser(
         formatter_class=argparse.ArgumentDefaultsHelpFormatter,
-- 
2.38.1