fix(example): mistakes in fuzz_x8664_linux binary

[chinggg]

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IMO, fuzz.c intended to read from stdin to buf and copy it to buf2, then print buf2 as string.
But there are two mistakes which do not affect the fuzzing result, I think they are typos:

• *buf = getc(stdin) == 'A' does not reads char, but the result of comparison
• printf(buf2) does not print buf2 as string

So I fix fuzz.c then compile it with gcc -g on Ubuntu 20.04 + gcc9.3, and modify the according address of main and stack_chk in fuzz_x8664_linux.py, it works as before.

If you think the fix is correct, the arm_qnx example may need fix as well.

[elicn]

Good catch!

[xwings]

Hey, thanks and welcome to Qiling !