Currently, when libtraceevent is not linked,
perf does not support tracepoint:

  # ./perf record -e sched:sched_switch -a sleep 10
  event syntax error: 'sched:sched_switch'
                       \___ unsupported tracepoint

  libtraceevent is necessary for tracepoint support
  Run 'perf list' for a list of valid events

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -e, --event <event>   event selector. use 'perf list' to list available events

For cross-compilation scenario, library may not be installed in the default
system path. Based on the above requirements, add LIBTRACEEVENT_DIR build
option to support specifying path of libtraceevent.

Example:

  1. Cross compile libtraceevent
  # cd /opt/libtraceevent
  # CROSS_COMPILE=aarch64-linux-gnu- make

  2. Cross compile perf
  # cd tool/perf
  # make VF=1 ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- NO_LIBELF=1 LDFLAGS=--static LIBTRACEEVENT_DIR=/opt/libtraceevent
  <SNIP>
  Auto-detecting system features:
  <SNIP>
  ...                       LIBTRACEEVENT_DIR: /opt/libtraceevent
Reviewed-by: Ian Rogers <irogers@google.com>
Signed-off-by: Yang Jihong <yangjihong@bytedance.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240314063000.2139877-1-yangjihong@bytedance.comSigned-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>