Add sample code to test trace_printk(). The trace_printk() functions should
never be used in production code. This makes testing it a bit more
difficult. Having a sample module that can test use cases of trace_printk()
can help out.
Currently it just tests trace_printk() where it will be converted into:
trace_bputs()
trace_puts()
trace_bprintk()
as well as staying as the normal _trace_printk().
It also tests its use in interrupt context as that will test the auxilery
buffers.
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>