HaikuDepot: Add missing stdlib.h include to fix the build.

src/apps/haikudepot/util/LocaleUtils.cpp

@@ -4,6 +4,7 @@
  */
 #include "LocaleUtils.h"
 
+#include <stdlib.h>
 
 #include <Collator.h>
 #include <Locale.h>
@@ -33,4 +34,4 @@ LocaleUtils::GetCollator(BCollator* collator)
 		debugger("unable to get the locale's collator");
 		exit(EXIT_FAILURE);
 	}
-}
+}