Remove redundant pam_set_item() call.

On Solaris 10, pam_set_item() call with an item value (char * for
current password, i.e. PAM_OLDAUTHTOK) that is taken from pam_get_item()
breaks the item content in PAM. (OSSTech ticket:26)

-- fumiyas, 2007-07-29

--- samba-3.0.24/source/nsswitch/pam_winbind.c.dist	2007-06-08 16:10:56.879997000 +0900
+++ samba-3.0.24.osstech/source/nsswitch/pam_winbind.c	2007-07-28 00:37:01.000000000 +0900
@@ -1280,12 +1280,6 @@ int pam_sm_chauthtok(pam_handle_t * pamh
 		}
 		
 		pam_set_data(pamh, PAM_WINBIND_PWD_LAST_SET, (void *)pwdlastset_prelim, NULL);
-
-		retval = pam_set_item(pamh, PAM_OLDAUTHTOK, (const void *) pass_old);
-		pass_old = NULL;
-		if (retval != PAM_SUCCESS) {
-			_pam_log(LOG_CRIT, "failed to set PAM_OLDAUTHTOK");
-		}
 	} else if (flags & PAM_UPDATE_AUTHTOK) {
 	
 		time_t pwdlastset_update = 0;