perf script: Remove duplicated code and needless script_spec__findnew()

perf script: Remove duplicated code and needless script_spec__findnew()

script_spec_register() called two functions: script_spec__find() and
script_spec__findnew().  But this way script_spec__find() gets called
two times, directly and via script_spec__findnew().

So remove script_spec__findnew() and make script_spec_register() only
call once script_spec__find().

Signed-off-by: Taeung Song <[email protected]>
Acked-by: Jiri Olsa <[email protected]>
Cc: Namhyung Kim <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>