perf bpf: Convert pid_map() to bpf_map()

First user, pid_t as the type, lets see how this goes with the BTF
routines.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Luis Cláudio Gonçalves <lclaudio@redhat.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: Yonghong Song <yhs@fb.com>
Link: https://lkml.kernel.org/n/tip-56eplvf86r69wt3p35nh805z@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/include/bpf/bpf.h

@@ -34,13 +34,7 @@ struct bpf_map SEC("maps") name = {				\
  *	  For the current need, 'perf trace --filter-pids', 64 should
  *	  be good enough, but this surely needs to be revisited.
  */
-#define pid_map(name, value_type)		\
-struct bpf_map SEC("maps") name = {		\
-	.type	     = BPF_MAP_TYPE_HASH,	\
-	.key_size    = sizeof(pid_t),		\
-	.value_size  = sizeof(value_type),	\
-	.max_entries = 64,			\
-}
+#define pid_map(name, value_type) bpf_map(name, HASH, pid_t, value_type, 64)
 
 static int (*bpf_map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags) = (void *)BPF_FUNC_map_update_elem;
 static void *(*bpf_map_lookup_elem)(struct bpf_map *map, void *key) = (void *)BPF_FUNC_map_lookup_elem;