perf lock: Use BPF for lock contention analysis

Add -b/--use-bpf option to use BPF to collect lock contention stats.
For simplicity it now runs system-wide and requires C-c to stop.
Upcoming changes will add the usual filtering.

  $ sudo perf lock con -b
  ^C
   contended   total wait     max wait     avg wait         type   caller

          42    192.67 us     13.64 us      4.59 us     spinlock   queue_work_on+0x20
          23     85.54 us     10.28 us      3.72 us     spinlock   worker_thread+0x14a
           6     13.92 us      6.51 us      2.32 us        mutex   kernfs_iop_permission+0x30
           3     11.59 us     10.04 us      3.86 us        mutex   kernfs_dop_revalidate+0x3c
           1      7.52 us      7.52 us      7.52 us     spinlock   kthread+0x115
           1      7.24 us      7.24 us      7.24 us     rwlock:W   sys_epoll_wait+0x148
           2      7.08 us      3.99 us      3.54 us     spinlock   delayed_work_timer_fn+0x1b
           1      6.41 us      6.41 us      6.41 us     spinlock   idle_balance+0xa06
           2      2.50 us      1.83 us      1.25 us        mutex   kernfs_iop_lookup+0x2f
           1      1.71 us      1.71 us      1.71 us        mutex   kernfs_iop_getattr+0x2c

Signed-off-by: Namhyung Kim <[email protected]>
Cc: Blake Jones <[email protected]>
Cc: Boqun Feng <[email protected]>
Cc: Davidlohr Bueso <[email protected]>
Cc: Ian Rogers <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Cc: Waiman Long <[email protected]>
Cc: Will Deacon <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

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