tests/vm: make --interactive (and therefore DEBUG=1) unconditional

While the concept of only dropping to ssh if a test fails is nice it
is more useful for this to be unconditional. You usually just want to
get the build up and running and then noodle around debugging or
attempting to replicate.

Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
diff --git a/tests/vm/basevm.py b/tests/vm/basevm.py
index 91a9226..0b8c1b2 100755
--- a/tests/vm/basevm.py
+++ b/tests/vm/basevm.py
@@ -403,7 +403,7 @@
     exitcode = 0
     if vm.ssh(*cmd) != 0:
         exitcode = 3
-    if exitcode != 0 and args.interactive:
+    if args.interactive:
         vm.ssh()
 
     if not args.snapshot: