perf/x86: Fix P6 FP_ASSIST event constraint

According to Intel SDM Volume 3B, FP_ASSIST is limited to Counter 1 only,
not Counter 0.

Tested on a Pentium II.
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1210191728570.14552@vincent-weaver-1.um.maine.eduSigned-off-by: Ingo Molnar <mingo@kernel.org>

arch/x86/kernel/cpu/perf_event_p6.c

@@ -34,7 +34,7 @@ static struct event_constraint p6_event_constraints[] =
 {
 	INTEL_EVENT_CONSTRAINT(0xc1, 0x1),	/* FLOPS */
 	INTEL_EVENT_CONSTRAINT(0x10, 0x1),	/* FP_COMP_OPS_EXE */
-	INTEL_EVENT_CONSTRAINT(0x11, 0x1),	/* FP_ASSIST */
+	INTEL_EVENT_CONSTRAINT(0x11, 0x2),	/* FP_ASSIST */
 	INTEL_EVENT_CONSTRAINT(0x12, 0x2),	/* MUL */
 	INTEL_EVENT_CONSTRAINT(0x13, 0x2),	/* DIV */
 	INTEL_EVENT_CONSTRAINT(0x14, 0x1),	/* CYCLES_DIV_BUSY */