perf augmented_syscalls: Convert to bpf_map()

To make the code more compact, end result is the same:

# perf trace -e /home/acme/git/perf/tools/perf/examples/bpf/augmented_syscalls.c sleep 1
0.000 ( 0.008 ms): sleep/9663 openat(dfd: CWD, filename: "/etc/ld.so.cache", flags: RDONLY|CLOEXEC) = 3
0.022 ( 0.005 ms): sleep/9663 openat(dfd: CWD, filename: "/lib64/libc.so.6", flags: RDONLY|CLOEXEC) = 3
0.226 ( 0.006 ms): sleep/9663 openat(dfd: CWD, filename: "/usr/lib/locale/locale-archive", flags: RDONLY|CLOEXEC) = 3
#

Cc: Adrian Hunter <[e-mail]>
Cc: Jiri Olsa <[e-mail]>
Cc: Luis Cláudio Gonçalves <[e-mail]>
Cc: Namhyung Kim <[e-mail]>
Cc: Wang Nan <[e-mail]>
Link: https://lkml.kernel.org/n/[e-mail]
Signed-off-by: Arnaldo Carvalho de Melo <[e-mail]>

tools/perf/examples/bpf/augmented_syscalls.c

···
 #include <stdio.h>
 #include <linux/socket.h>
 
-struct bpf_map SEC("maps") __augmented_syscalls__ = {
-       .type = BPF_MAP_TYPE_PERF_EVENT_ARRAY,
-       .key_size = sizeof(int),
-       .value_size = sizeof(u32),
-       .max_entries = __NR_CPUS__,
-};
+/* bpf-output associated map */
+bpf_map(__augmented_syscalls__, PERF_EVENT_ARRAY, int, u32, __NR_CPUS__);
 
 struct syscall_exit_args {
 	unsigned long long common_tp_fields;