tracing: Convert module refcnt events to DEFINE_EVENT

Use DECLARE_EVENT_CLASS to remove duplicate code:

   text    data     bss     dec     hex filename
  29854    1980     128   31962    7cda kernel/module.o.old
  28750    1980     128   30858    788a kernel/module.o

Two events are converted:

  module_refcnt: module_get, module_put

No change in functionality.

Signed-off-by: Li Zefan <lizf@cn.fujitsu.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <4B0E283B.3010508@cn.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>