Avoid use of tools/perf/include/bpf/bpf.h and use the more regular BPF
headers.

Committer testing:

  # perf trace -e ~acme/git/perf/tools/perf/examples/bpf/5sec.c sleep 5
       0.000 perf_bpf_probe:hrtimer_nanosleep(__probe_ip: -1474734416, rqtp: 5000000000)
  # perf trace -e ~acme/git/perf/tools/perf/examples/bpf/5sec.c/max-stack=7/ sleep 5
       0.000 perf_bpf_probe:hrtimer_nanosleep(__probe_ip: -1474734416, rqtp: 5000000000)
                                         hrtimer_nanosleep ([kernel.kallsyms])
                                         common_nsleep ([kernel.kallsyms])
                                         __x64_sys_clock_nanosleep ([kernel.kallsyms])
                                         do_syscall_64 ([kernel.kallsyms])
                                         entry_SYSCALL_64_after_hwframe ([kernel.kallsyms])
                                         __GI___clock_nanosleep (/usr/lib64/libc.so.6)
                                         [0] ([unknown])
  #
Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: https://lore.kernel.org/r/20221103045437.163510-7-irogers@google.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>