[LTP] lib: Rename function check_kver() => check_min_kver()

[Petr Vorel]

Hi Andrea,

> Hi Petr,

> > @Cyril @Andrea could you also please double check?

> It's correct.

> The legacy ETXTBSY behavior was fully restored in commit
> 3b832035387f (Revert "fs: don't block i_writecount during exec").

Thanks!

> So we have a window where this is not valid anymore and we should
> take this in consideration inside the test.

In that case we want to have both in a single commit, right?
=> yet another version.

Kind regards,
Petr

> Regards,