* man/pwconv.8.xml: Fix typos.

* man/chpasswd.8.xml, man/chgpasswd.8.xml: Document the NONE crypt
  method.
* man/login.defs.d/MAIL_DIR.xml: Add comment regarding useradd not
  using MAIL_FILE.
* man/login.defs.d/ERASECHAR.xml, man/login.defs.d/KILLCHAR.xml,
  man/login.defs.d/CONSOLE_GROUPS.xml, man/login.defs.d/ENV_HZ.xml,
  man/login.defs.d/ENV_PATH.xml, man/login.defs.d/ENV_SUPATH.xml:
  These variables are also used by some tools when compiled with PAM
  support.
* man/login.defs.d/ENV_HZ.xml: Add note that it is only used by
  sulogin when compiled with PAM support.
* man/login.defs.d/ENV_SUPATH.xml: Typos: ENV_PATH -> ENV_SUPATH,
  and mention sbin in the path.
* man/login.defs.d/LOGIN_STRING.xml: Fix typo: confition ->
  condition.
* man/sg.1.xml: Add CONFIGURATION section (SYSLOG_SG_ENAB).
* man/su.1.xml: ENV_HZ, LOGIN_STRING, MAIL_DIR, USERGROUPS_ENAB
  are only used when su is compiled without PAM support.
* man/login.defs.5.xml: Added variables: OBSCURE_CHECKS_ENAB
  PASS_ALWAYS_WARN PASS_CHANGE_TRIES SULOG_FILE SU_NAME
  SU_WHEEL_ONLY SYSLOG_SG_ENAB SYSLOG_SU_ENAB.
* man/login.defs.5.xml: ENVIRON_FILE is only used when compiled
  without PAM support.
* man/login.defs.5.xml: sulogin uses variables even when compiled
  with PAM support.
* man/login.1.xml: ENV_HZ ENV_PATH ENV_SUPATH MAIL_DIR UMASK are
  only used when login is not compiled with PAM support.

man/su.1.xml

@@ -203,20 +203,20 @@
       &CONSOLE;
       &CONSOLE_GROUPS;
       &DEFAULT_HOME;
-      &ENV_HZ;
+      <phrase condition="no_pam">&ENV_HZ;</phrase>
       &ENVIRON_FILE;
       &ENV_PATH;
       &ENV_SUPATH;
       &ENV_TZ;
-      &LOGIN_STRING;
+      <phrase condition="no_pam">&LOGIN_STRING;</phrase>
       &MAIL_CHECK_ENAB;
-      &MAIL_DIR;
+      <phrase condition="no_pam">&MAIL_DIR;</phrase>
       &QUOTAS_ENAB;
       &SULOG_FILE;
       &SU_NAME;
       &SU_WHEEL_ONLY;
       &SYSLOG_SU_ENAB;
-      &USERGROUPS_ENAB;
+      <phrase condition="no_pam">&USERGROUPS_ENAB;</phrase>
     </variablelist>
   </refsect1>