x86, perf: Add raw events support for the P4 PMU

The adding of raw event support lead to complete code
refactoring. I hope is became more readable then it was.

The list of changes:

1)  The 64bit config field is enough to hold all information we need
    to track event details. To achieve it we used *own* enum for
    events selection in ESCR register and map this key into proper
    value at moment of event enabling.

    For the same reason we use 12LSB bits in CCCR register -- to track
    which exactly cache trace event was requested. And we cear this bits
    at real 'write' moment.

2)  There is no per-cpu area reserved for P4 PMU anymore. We
    don't need it. All is held by config.

3)  Now we may use any available counter, ie we try to grab any
    possible counter.

v2:
  - Lin Ming reported the lack of ESCR selector in CCCR for cache events

v3:
  - Don't loose cache event codes at config unpacking procedure, we may
    need it one day so no obscure hack behind our back, better to clear
    reserved bits explicitly when needed (thanks Ming for pointing out)

  - Lin Ming fixed misplaced opcodes in cache events

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Tested-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Cyrill Gorcunov <gorcunov@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1269403766.3409.6.camel@minggr.sh.intel.com>
[ v4: did a few whitespace fixlets ]
Signed-off-by: Ingo Molnar <mingo@elte.hu>