[dovecot/core] 827506: lib: Fix returning error from unlink_directory()

[GitHub]

  Branch: refs/heads/master
  Home:   https://github.com/dovecot/core
  Commit: 827506061489ec174922bbecef9d09671b74c357
      https://github.com/dovecot/core/commit/827506061489ec174922bbecef9d09671b74c357
  Author: Timo Sirainen <timo.sirainen at dovecot.fi>
  Date:   2018-04-27 (Fri, 27 Apr 2018)

  Changed paths:
    M src/lib/unlink-directory.c

  Log Message:
  -----------
  lib: Fix returning error from unlink_directory()

On non-ENOENT errors it was returning 1 instead of -1.