s3:winbindd: Fix winbindd child logfile name handling

s3:winbindd: Fix winbindd child logfile name handling

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14852

Handling of logfile name for main and child winbindd must ensure:

1) Log directory is selected in this order:
  * -l option of winbindd
  * "log file" parameter in smb.conf
  * compile time value '/usr/local/samba/var'

2) Log filename pattern
  * parent process uses log.winbindd
  * child uses log.wb-<name>

3) Log reopen works for both parent and child (i.e. log filename is not changed)
  * kill -HUP <pid>
  * smbcontrol <pid> reload-config

This commit removes 3 calls of is_default_dyn_LOGFILEBASE() to make sure that:
  - 1st removal: child uses log.wb-<name> after the fork
  - 2nd removal: child after HUP signal, does not switch to log.winbindd
  - 3rd removal: child after smbcontrol reload-config, does not switch to
    log.winbindd

Interesting commits: bfa1b2a8 1484b7f3 3b015a4c d1f7a371

Signed-off-by: Pavel Filipenský <pfilipen@redhat.com>
Reviewed-by: Ralph Boehme <slow@samba.org>
Reviewed-by: Andreas Schneider <asn@samba.org>