zlog_init: Initializing zlog with a path to a directory doesn't result in an error

[iancuivasciuc]

If we try to initialize zlog with a wrong path to a file, we will get an error. Instead, if we try to initialize zlog with a wrong path which points to a valid directory, we won't get any error. It would be the same as if we tried to initialized it with an empty file.

[dotnwat]

Thanks for the report. Happy to accept PRs that fix any issues.

[iancuivasciuc]

I made a mistake. I wanted to create an issue to another zlog project.