perf hists browser: Fix output for 100.00%

Current hpp format functions assume that the output will fit to 6
character including % sign (XX.YY%) so used "%5.2f%%" as a format
string.  However it might be the case if collapsing resulted in a single
entry which has 100.00% (7 character) of period. In this case the output
will be shifted by 1 character.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347431706-7839-1-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>