perf evlist: Document missing --force option

Add --force to the man page.

Signed-off-by: Sihyeon Jang <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Link: http://lkml.kernel.org/r/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/Documentation/perf-evlist.txt

···
 --input=::
         Input file name. (default: perf.data unless stdin is a fifo)
 
+-f::
+--force::
+	Don't complain, do it.
+
 -F::
 --freq=::
 	Show just the sample frequency used for each event.