perf_events: Check for filters on fixed counter events

Intel fixed counters do not support all the filters possible with a
generic counter. Thus, if a fixed counter event is passed but with
certain filters set, then the fixed_mode_idx() function must fail
and the event must be measured in a generic counter instead.

Reject filters are: inv, edge, cnt-mask.

Signed-off-by: Stephane Eranian <eranian@gmail.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1254840129-6198-2-git-send-email-eranian@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>