patch 8.2.3274: macro for printf format check can be simplified

Problem:    Macro for printf format check can be simplified.
Solution:   Add ATTRIBUTE_FORMAT_PRINTF(). (Dominique Pellé, issue #8635)
diff --git a/src/nbdebug.h b/src/nbdebug.h
index e1bb171..9a47c3a 100644
--- a/src/nbdebug.h
+++ b/src/nbdebug.h
@@ -42,11 +42,7 @@
 } WtWait;
 
 
-void		 nbdbg(char *, ...)
-# ifdef USE_PRINTF_FORMAT_ATTRIBUTE
-   __attribute__((format(printf, 1, 2)))
-# endif
-;
+void		 nbdbg(char *, ...) ATTRIBUTE_FORMAT_PRINTF(1, 2);
 
 void nbdebug_wait(u_int wait_flags, char *wait_var, u_int wait_secs);
 void nbdebug_log_init(char *log_var, char *level_var);