No output for kprobes

Hi!

I've built bpftools (including bpftrace) for aach64.

```sh
# /data/bin/bpftools/bpftrace --info
System
OS: Linux 5.10.43 #9 SMP PREEMPT Tue Jun 27 12:32:32 UTC 2023
Arch: aarch64

Build
version: v0.16.0-96-g58bd
LLVM: 14.0.6
unsafe uprobe: no
bfd: no
libdw (DWARF support): no

Kernel helpers
probe_read: yes
probe_read_str: yes
probe_read_user: yes
probe_read_user_str: yes
probe_read_kernel: yes
probe_read_kernel_str: yes
get_current_cgroup_id: yes
send_signal: yes
override_return: yes
get_boot_ns: yes
dpath: no
skboutput: no

Kernel features
Instruction limit: 1000000
Loop support: yes
btf: no
map batch: yes
uprobe refcount (depends on Build:bcc bpf_attach_uprobe refcount): no

Map types
hash: yes
percpu hash: yes
array: yes
percpu array: yes
stack_trace: yes
perf_event_array: yes

Probe types
kprobe: yes
tracepoint: yes
perf_event: yes
kfunc: no
iter:task: no
iter:task_file: no
kprobe_multi: no
raw_tp_special: yes
```

Tracepoints are caught fine, but I can't get any output for kernel probes (kprobes).

```sh
# ./strace -ebpf /data/bin/bpftools/bpftrace -e 'kprobe:do_nanosleep { printf("function is called\n"); }' -v
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=17585, si_uid=0, si_status=0, si_utime=1, si_stime=0} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=17589, si_uid=0, si_status=0, si_utime=0, si_stime=1} ---
--- SIGCHLD {si_signo=SIGCHLD, si_code=CLD_EXITED, si_pid=17591, si_uid=0, si_status=0, si_utime=0, si_stime=0} ---
bpf(0x17 /* BPF_??? */, 0x7fccfe4410, 12) = -1 ENOENT (No such file or directory)
bpf(0x17 /* BPF_??? */, 0x7fccfe3f50, 12) = -1 ENOENT (No such file or directory)
INFO: node count: 6
Attaching 1 probe...
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_SOCKET_FILTER, insn_cnt=2, insns=0x7fccfe40e0, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(0, 0, 0), prog_flags=0, prog_name="", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 116) = -1 EINVAL (Invalid argument)
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_SOCKET_FILTER, insn_cnt=2, insns=0x7fccfe40f0, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(0, 0, 0), prog_flags=0, prog_name="libbpf_nametest"}, 64) = 3
bpf(BPF_MAP_CREATE, {map_type=BPF_MAP_TYPE_PERF_EVENT_ARRAY, key_size=4, value_size=4, max_entries=8, map_flags=0, inner_map_fd=0, map_name="printf", map_ifindex=0}, 72) = 3
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_MAP_UPDATE_ELEM, {map_fd=3, key=0x7fccfe461c, value=0x7fccfe45dc, flags=BPF_ANY}, 32) = 0
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_KPROBE, insn_cnt=2, insns=0x7fccfe4030, license="GPL", log_level=0, log_size=0, log_buf=NULL, kern_version=KERNEL_VERSION(0, 0, 0), prog_flags=0, prog_name="ksys_read", prog_ifindex=0, expected_attach_type=0x2a /* BPF_??? */}, 128) = 13
bpf(0x1c /* BPF_??? */, 0x7fccfe3ea0, 48) = -1 EINVAL (Invalid argument)
bpf(BPF_PROG_LOAD, {prog_type=BPF_PROG_TYPE_KPROBE, insn_cnt=12, insns=0xb400007771a0b320, license="GPL", log_level=1, log_size=1000000, log_buf="", kern_version=KERNEL_VERSION(5, 10, 43), prog_flags=0, prog_name="do_nanosleep", prog_ifindex=0, expected_attach_type=BPF_CGROUP_INET_INGRESS}, 128) = 14
bpf(BPF_OBJ_GET_INFO_BY_FD, {info={bpf_fd=14, info_len=232 => 208, info=0x7fccfe41d0}}, 16) = 0

Program ID: 86

The verifier log:
processed 10 insns (limit 1000000) max_states_per_insn 0 total_states 0 peak_states 0 mark_read 0

Attaching kprobe:do_nanosleep
```

Currently kernel is built with flags (+ `CONFIG_IKHEADERS`) specified in [check_kernel_features.sh](https://github.com/iovisor/bpftrace/blob/master/scripts/check_kernel_features.sh) except `CONFIG_BPF_JIT`, `CONFIG_UPROBES` and `CONFIG_UPROBE_EVENTS`.

Could you please suggest what can be a reason of such behavior if you've faced with the similar problem? Or what steps can be done to troubleshot it?

Thanks!