perf annotate browser: Help for cycling thru hottest instructions with TAB/shift+TAB

The popup help accessed via 'h' wasn't mentioning about TAB and
shift-TAB, just about 'H', which goes to the hottest line, while the
former two are the hotkeys for actually cycling thru the hottest lines.

Reported-by: Flavio Bruno Leitner <fbl@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Taeung Song <treeze.taeung@gmail.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-5ppym6odizfj1ifa4t7neiku@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/browsers/annotate.c

@@ -829,7 +829,8 @@ static int annotate_browser__run(struct annotate_browser *browser,
 		"q/ESC/CTRL+C  Exit\n\n"
 		"ENTER         Go to target\n"
 		"ESC           Exit\n"
-		"H             Cycle thru hottest instructions\n"
+		"H             Go to hottest instruction\n"
+		"TAB/shift+TAB Cycle thru hottest instructions\n"
 		"j             Toggle showing jump to target arrows\n"
 		"J             Toggle showing number of jump sources on targets\n"
 		"n             Search next string\n"