Fix coding style issue

Replace:

  if (-1 == foo())

with:

  if (foo() == -1)

While this coding style is not in direct contravention of our currently
ratified CODING_STYLE treaty, it could be argued that the Article 3 of
the European Convention on Human Rights (prohibiting torture and "inhuman
or degrading treatment") reads on the matter.

[This commit message was brought to you without humour, as is evidenced
by the absence of any emoticons]

Signed-off-by: Mark McLoughlin <markmc@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Blue Swirl <blauwirbel@gmail.com>
diff --git a/qemu-config.c b/qemu-config.c
index 39bf6a9..555c7ba 100644
--- a/qemu-config.c
+++ b/qemu-config.c
@@ -186,7 +186,7 @@
         return -1;
     }
 
-    if (-1 == qemu_opt_set(opts, arg, str+offset+1)) {
+    if (qemu_opt_set(opts, arg, str+offset+1) == -1) {
         fprintf(stderr, "failed to set \"%s\" for %s \"%s\"\n",
                 arg, lists[i]->name, id);
         return -1;