Fix wrong var name

--- configure.in
+++ configure.in
@@ -165,7 +165,7 @@ AC_DEFINE_UNQUOTED(_UTMP_FILE, "$shadow_
 
 AC_CACHE_CHECK([location of faillog/lastlog/wtmp], shadow_cv_logdir,
 [for shadow_cv_logdir in /var/log /var/adm /usr/adm /etc; do
-	if test -d $logdir; then
+	if test -d $shadow_cv_logdir; then
 		break
 	fi
 done])
--- configure
+++ configure
@@ -22349,7 +22348,7 @@
   echo $ECHO_N "(cached) $ECHO_C" >&6
 else
   for shadow_cv_logdir in /var/log /var/adm /usr/adm /etc; do
-	if test -d $logdir; then
+	if test -d $shadow_cv_logdir; then
 		break
 	fi
 done