tracing: not necessary to define DEFINE_EVENT_PRINT to be empty again

After the previous cleanup, DEFINE_EVENT_PRINT's definition has no
relationship with DEFINE_EVENT. So After we re-define DEFINE_EVENT, it
is not necessary to define DEFINE_EVENT_PRINT to be empty again.

Link: http://lkml.kernel.org/r/20200612092844.56107-5-richard.weiyang@linux.alibaba.com



Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>