perf: Power7: Make CPI stack events available in sysfs

A set of Power7 events are often used for Cycles Per Instruction (CPI) stack
analysis. Make these events available in sysfs (/sys/devices/cpu/events/) so
they can be identified using their symbolic names:

	perf stat -e 'cpu/PM_CMPLU_STALL_DCACHE_MISS/' /bin/ls

Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Acked-by: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: linuxppc-dev@ozlabs.org
Link: http://lkml.kernel.org/r/20130406164803.GA408@us.ibm.com


Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>