perf, tool: Allow to use hw events in PMU syntax

hi,
here's the change to make following syntax available:
  perf stat -e cpu/event=instructions/u ls

this is identical to:
  perf stat -e instructions:u ls

v2 changes:
  - making the hw events translations available under the 'events',
    the userspace trnaslation is then done by existing term aliasing
    code with some little tweeks ;)
  - patches 1-3 are independent fixies

Attached patches:
  01/10 perf, tool: Add empty rule for new line in event syntax parsing
  02/10 perf, tool: Fix pmu object initialization
  03/10 perf, tool: Properly free format data
  04/10 perf, x86: Making hardware events translations available in sysfs
  05/10 perf, tool: Split out PE_VALUE_SYM parsing token to SW and HW tokens
  06/10 perf, tool: Split event symbols arrays to hw and sw parts
  07/10 perf, tool: Add support to specify hw event as pmu event term
  08/10 perf, tool: Add sysfs read file interface
  09/10 perf, test: Use ARRAY_SIZE in parse events tests
  10/10 perf, test: Add automated tests for pmu sysfs translated events

jirka
---
 arch/x86/kernel/cpu/perf_event.c    |   44 ++++++++++++++
 tools/perf/util/parse-events-test.c |  158 ++++++++++++++++++++++++++++++++++++++++++++------
 tools/perf/util/parse-events.c      |  203 +++++++++++++++++++++++++++++++++++++++++++++++------------------
 tools/perf/util/parse-events.h      |    2 +
 tools/perf/util/parse-events.l      |    3 +-
 tools/perf/util/parse-events.y      |   24 ++++++--
 tools/perf/util/pmu.c               |   60 ++++++++++++-------
 tools/perf/util/sysfs.c             |   19 ++++++
 tools/perf/util/sysfs.h             |    1 +
 9 files changed, 413 insertions(+), 101 deletions(-)