perf record: Get rid of -l option from Documentation

The perf record does not support -l option anymore, so nuke it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1425272038-10406-1-git-send-email-namhyung@kernel.orgSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/Documentation/perf-record.txt

@@ -62,9 +62,6 @@ OPTIONS
 --all-cpus::
         System-wide collection from all CPUs.
 
--l::
-        Scale counter values.
-
 -p::
 --pid=::
 	Record events on existing process ID (comma separated list).