perf c2c: Fix spelling mistakes in browser help text

Togle -> Toggle, lenght -> length.

Signed-off-by: Kim Phillips <kim.phillips@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20171114150447.f4b63bc5d97c83cdaa8bf7dc@arm.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>