tracing: Move conditional into update_funcs() in recordmcount.pl

Move all the condition validations into the function update_funcs().
Also update_funcs should not die if $ref_func is undefined for there may be
more than one valid section in an object file.

Signed-off-by: Li Hong <lihong.hi@gmail.com>
LKML-Reference: <20091028050703.GG30758@uhli>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>