Add strace filtering

[OFFTKP]

Our guest strace (FELIX86_STRACE, FELIX86_STRACE_ERRORS) should allow filtering so that only specific syscalls print. Should also allow to disable certain syscalls. Something similar to what the actual strace binary does with -e trace=...

[ArchCipher]

Hi! I would like to take this on as my first issue.
Could you please explain this a bit further?
Does this mean extending FELIX86_STRACE, FELIX86_STRACE_ERRORS to support filtering similar to -e trace=..., is this understanding correct?

[OFFTKP]

Yes. It is currently a boolean value in config, it should be turned into a string that takes syscall names as options

E.g.:
FELIX86_STRACE=read,open

But it should also continue to support FELIX86_STRACE=1 which would mean all syscalls as it means right now.