We must include gettext.h before missing.h as it includes system

headers.  Also add missing DEFAULT_TEXT_DOMAIN defines in sudoers
audit code that does not include sudoers.h.

common/sudo_debug.c

@@ -47,6 +47,9 @@
 #include <fcntl.h>
 #include <time.h>
 
+#define DEFAULT_TEXT_DOMAIN	"sudo"
+#include "gettext.h"		/* must be included before missing.h */
+
 #include "missing.h"
 #include "alloc.h"
 #include "fatal.h"
@@ -54,9 +57,6 @@
 #include "sudo_debug.h"
 #include "sudo_util.h"
 
-#define DEFAULT_TEXT_DOMAIN	"sudo"
-#include "gettext.h"
-
 /*
  * The debug priorities and subsystems are currently hard-coded.
  * In the future we might consider allowing plugins to register their