selftests/bpf: remove bpf_util.h from BPF C progs

Though currently there is no problem including bpf_util.h in kernel
space BPF C programs, in next patch in this stack, I will reuse
libbpf_num_possible_cpus() in bpf_util.h thus include libbpf.h in it,
which will cause BPF C programs compile error. Therefore I will first
remove bpf_util.h from all test BPF programs.

This can also make it clear that bpf_util.h is a user-space utility
while bpf_helpers.h is a kernel space utility.
Signed-off-by: Hechao Li <hechaol@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

tools/testing/selftests/bpf/bpf_endian.h

@@ -2,6 +2,7 @@
 #ifndef __BPF_ENDIAN__
 #define __BPF_ENDIAN__
 
+#include <linux/stddef.h>
 #include <linux/swab.h>
 
 /* LLVM's BPF target selects the endianness of the CPU

tools/testing/selftests/bpf/progs/sockmap_parse_prog.c

 #include <linux/bpf.h>
 #include "bpf_helpers.h"
-#include "bpf_util.h"
 #include "bpf_endian.h"
 
 int _version SEC("version") = 1;

tools/testing/selftests/bpf/progs/sockmap_tcp_msg_prog.c

 #include <linux/bpf.h>
+
 #include "bpf_helpers.h"
-#include "bpf_util.h"
 #include "bpf_endian.h"
 
 int _version SEC("version") = 1;

tools/testing/selftests/bpf/progs/sockmap_verdict_prog.c

 #include <linux/bpf.h>
 #include "bpf_helpers.h"
-#include "bpf_util.h"
 #include "bpf_endian.h"
 
 int _version SEC("version") = 1;

tools/testing/selftests/bpf/progs/test_sysctl_prog.c

@@ -8,7 +8,6 @@
 #include <linux/bpf.h>
 
 #include "bpf_helpers.h"
-#include "bpf_util.h"
 
 /* Max supported length of a string with unsigned long in base 10 (pow2 - 1). */
 #define MAX_ULONG_STR_LEN 0xF
@@ -16,6 +15,10 @@
 /* Max supported length of sysctl value string (pow2). */
 #define MAX_VALUE_STR_LEN 0x40
 
+#ifndef ARRAY_SIZE
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))
+#endif
+
 static __always_inline int is_tcp_mem(struct bpf_sysctl *ctx)
 {
 	char tcp_mem_name[] = "net/ipv4/tcp_mem";