[openEuler-1.0-LTS] BPF 重复注册 tracepoint 触发 WARNING

构造的bpf syscall用例可以重复注册完全相同的tracepoint导致触发WARNING
影响bpf syscall注册tracepoint，如果发生了重复注册就会报WARNING
https://syzkaller.appspot.com/bug?id=41f4318cf01762389f4d1c1c459da4f542fe5153

复现程序：

```
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#ifndef __NR_bpf
#define __NR_bpf 321
#endif

#define BITMASK(bf_off, bf_len) (((1ull << (bf_len)) - 1) << (bf_off))
#define STORE_BY_BITMASK(type, htobe, addr, val, bf_off, bf_len)               \
  *(type*)(addr) =                                                             \
      htobe((htobe(*(type*)(addr)) & ~BITMASK((bf_off), (bf_len))) |           \
            (((type)(val) << (bf_off)) & BITMASK((bf_off), (bf_len))))

uint64_t r[1] = {0xffffffffffffffff};

int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  intptr_t res = 0;
  *(uint32_t*)0x20000280 = 0x11;
  *(uint32_t*)0x20000284 = 3;
  *(uint64_t*)0x20000288 = 0x20000180;
  *(uint8_t*)0x20000180 = 0x18;
  STORE_BY_BITMASK(uint8_t, , 0x20000181, 0, 0, 4);
  STORE_BY_BITMASK(uint8_t, , 0x20000181, 0, 4, 4);
  *(uint16_t*)0x20000182 = 0;
  *(uint32_t*)0x20000184 = 0;
  *(uint8_t*)0x20000188 = 0;
  *(uint8_t*)0x20000189 = 0;
  *(uint16_t*)0x2000018a = 0;
  *(uint32_t*)0x2000018c = 0;
  *(uint8_t*)0x20000190 = 0x95;
  *(uint8_t*)0x20000191 = 0;
  *(uint16_t*)0x20000192 = 0;
  *(uint32_t*)0x20000194 = 0;
  *(uint64_t*)0x20000290 = 0x20000040;
  memcpy((void*)0x20000040, "syzkaller\000", 10);
  *(uint32_t*)0x20000298 = 1;
  *(uint32_t*)0x2000029c = 0xc9;
  *(uint64_t*)0x200002a0 = 0x20000080;
  *(uint32_t*)0x200002a8 = 0;
  *(uint32_t*)0x200002ac = 0;
  memset((void*)0x200002b0, 0, 16);
  *(uint32_t*)0x200002c0 = 0;
  *(uint32_t*)0x200002c4 = 0;
  *(uint32_t*)0x200002c8 = -1;
  *(uint32_t*)0x200002cc = 8;
  *(uint64_t*)0x200002d0 = 0;
  *(uint32_t*)0x200002d8 = 0;
  *(uint32_t*)0x200002dc = 0x10;
  *(uint64_t*)0x200002e0 = 0;
  *(uint32_t*)0x200002e8 = 0;
  *(uint32_t*)0x200002ec = 0;
  *(uint32_t*)0x200002f0 = 0;
  *(uint32_t*)0x200002f4 = 0;
  *(uint64_t*)0x200002f8 = 0;
  res = syscall(__NR_bpf, 5ul, 0x20000280ul, 0x80ul);
  if (res != -1)
    r[0] = res;
  *(uint64_t*)0x200001c0 = 0x20000000;
  memcpy((void*)0x20000000, "writeback_sb_inodes_requeue\000", 28);
  *(uint32_t*)0x200001c8 = r[0];
  syscall(__NR_bpf, 0x11ul, 0x200001c0ul, 0x10ul);
  *(uint64_t*)0x200001c0 = 0x20000000;
  memcpy((void*)0x20000000, "writeback_sb_inodes_requeue\000", 28);
  *(uint32_t*)0x200001c8 = r[0];
  syscall(__NR_bpf, 0x11ul, 0x200001c0ul, 0x10ul);
  return 0;
}
```

GVP openEuler/kernel

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GVPopenEuler/kernel

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