Make ncurses-config report the correct directory for ncurses.h.

--- configure	2007/10/29 13:59:32	1.9
+++ configure	2007/10/29 14:18:12
@@ -5253,6 +5253,7 @@
 fi;
 echo "$as_me:5254: result: $with_overwrite" >&5
 echo "${ECHO_T}$with_overwrite" >&6
+WITH_OVERWRITE="$with_overwrite"
 
 echo "$as_me:5257: checking if external terminfo-database is used" >&5
 echo $ECHO_N "checking if external terminfo-database is used... $ECHO_C" >&6