[BUG]24-hide libbpf: failed to find BTF info for global/extern symbol 'pid_to_hide'

[zer0-1s]

Describe the bug
A clear and concise description of what the bug is.
在编译 24-hide 代码时，编译错误

598 warnings generated.
libbpf: failed to find BTF info for global/extern symbol 'pid_to_hide'
Error: failed to link '.output/pidhide.tmp.bpf.o': No such file or directory (2)
make: *** [Makefile:112: .output/pidhide.bpf.o] Error 254
make: *** Deleting file '.output/pidhide.bpf.o'

To Reproduce
Steps to reproduce the behavior:

cd src/24-hide
make

Expected behavior
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Screenshots
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Desktop (please complete the following information):

• Ubuntu 20.04
• Linux version 5.15.0-124-generic
• clang version 10.0.0-4ubuntu1

Additional context

Add any other context about the problem here.

https://lore.kernel.org/bpf/CAEf4BzZnZ=jqTxShQ7p2tp=0sT5iMEJVB+zqhf55XtwQHOODtA@mail.gmail.com/T/

有一个patch与此类似

[zer0-1s]

修改pidhide.bpf.c

const volatile char pid_to_hide[MAX_PID_LEN] = "";

参考patch可以修改，完成编译操作