bugfix: fixed errors and warnings with C compilers without variadic macro support.

Author: agentzh

src/ddebug.h

@@ -19,7 +19,8 @@
 
 #include <stdarg.h>
 
-static void dd(const char* fmt, ...) {
+static ngx_inline void
+dd(const char* fmt, ...) {
 }
 
 #    endif
@@ -34,7 +35,8 @@ static void dd(const char* fmt, ...) {
 
 #include <stdarg.h>
 
-static void dd(const char* fmt, ...) {
+static ngx_inline void
+dd(const char* fmt, ...) {
 }
 
 #   endif