Clean up test for qdev_init() failure

Some callers test for != 0, some for < 0.  Normalize to < 0.

Patchworks-ID: 35171
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
diff --git a/hw/ide/isa.c b/hw/ide/isa.c
index 3205f40..9f0fdd6 100644
--- a/hw/ide/isa.c
+++ b/hw/ide/isa.c
@@ -85,7 +85,7 @@
     qdev_prop_set_uint32(&dev->qdev, "iobase",  iobase);
     qdev_prop_set_uint32(&dev->qdev, "iobase2", iobase2);
     qdev_prop_set_uint32(&dev->qdev, "irq",     isairq);
-    if (qdev_init(&dev->qdev) != 0)
+    if (qdev_init(&dev->qdev) < 0)
         return -1;
 
     s = DO_UPCAST(ISAIDEState, dev, dev);