perf tools: Fix hw breakpoint's type modifier parsing

Fixing the hw breakpoint's type modifier parsing to allow all possible
combinations of 'rwx' characters.

Adding automated tests to the parsing test suite.

Reported-by: Jovi Zhang <bookjovi@gmail.com>
Original-patch-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Jovi Zhang <bookjovi@gmail.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/20120629072254.GA940@krava.brq.redhat.com


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