Adds perf events support for L2 cache PMU.
The L2 cache PMU driver is named 'l2cache_0' and can be used
with perf events to profile L2 events such as cache hits
and misses on Qualcomm Technologies processors.
Reviewed-by: Mark Rutland <firstname.lastname@example.org>
Signed-off-by: Neil Leeder <email@example.com>
[will: minimise nesting in l2_cache_associate_cpu_with_cluster]
[will: use kstrtoul for unsigned long, remove redunant .owner setting]
Signed-off-by: Will Deacon <firstname.lastname@example.org>