build: fix mingw printing of pid

Commit c7542573 introduced a compilation failure:

../../src/access/viraccessdriverpolkit.c: In function 'virAccessDriverPolkitCheck':
../../src/access/viraccessdriverpolkit.c:137:5: error: format '%d' expects argument of type 'int', but argument 9 has type 'pid_t' [-Werror=format=]
     VIR_DEBUG("Check action '%s' for process '%d' time %lld uid %d",
     ^

Since mingw pid_t is 64 bits, it's easier to just follow what we've
done elsewhere and cast to a large enough type when printing pids.

* src/access/viraccessdriverpolkit.c (virAccessDriverPolkitCheck):
Add cast.
Signed-off-by: NEric Blake <eblake@redhat.com>

src/access/viraccessdriverpolkit.c

 /*
- * viraccessdriverpolkit.c: polkited access control driver
+ * viraccessdriverpolkit.c: polkitd access control driver
  *
  * Copyright (C) 2012, 2014 Red Hat, Inc.
  *
@@ -134,8 +134,8 @@ virAccessDriverPolkitCheck(virAccessManagerPtr manager ATTRIBUTE_UNUSED,
                                        &uid) < 0)
         goto cleanup;
 
-    VIR_DEBUG("Check action '%s' for process '%d' time %lld uid %d",
-              actionid, pid, startTime, uid);
+    VIR_DEBUG("Check action '%s' for process '%lld' time %lld uid %d",
+              actionid, (long long) pid, startTime, uid);
 
     rv = virPolkitCheckAuth(actionid,
                             pid,