perf tools: Add support to new style format of kernel PMU event

Add new rules for kernel PMU event.

Currently, the patch only want to handle the PMU event name as "a-b" and
"a".

event_pmu:
PE_KERNEL_PMU_EVENT sep_dc
|
PE_PMU_EVENT_PRE '-' PE_PMU_EVENT_SUF sep_dc

PE_KERNEL_PMU_EVENT token is for
cycles-ct/cycles-t/mem-loads/mem-stores.

The prefix cycles is mixed up with cpu-cycles.  loads and stores are
mixed up with cache event So they have to be hardcode in lex.

PE_PMU_EVENT_PRE and PE_PMU_EVENT_SUF tokens are for other PMU events.

The lex looks generic identifier up in the table and return the matched
token. If there is no match, generic PE_NAME token will be return.

Using the rules, kernel PMU event could use new style format without //

so you can use:

  perf record -e mem-loads ...

instead of:

  perf record -e cpu/mem-loads/

Signed-off-by: Kan Liang <kan.liang@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lkml.kernel.org/r/1412694532-23391-4-git-send-email-kan.liang@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>