perf include bpf: Add bpf_tail_call() prototype

Will be used together with BPF_MAP_TYPE_PROG_ARRAY in
tools/perf/examples/bpf/augmented_raw_syscalls.c.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Link: https://lkml.kernel.org/n/tip-pd1bpy8i31nta6jqwdex871g@git.kernel.org


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