Fix build with split tinfow library.

--- a/configure.in
+++ b/configure.in
@@ -31,6 +31,7 @@
     [
 	#use unicode ncursesw (default case)
 	AC_CHECK_LIB(ncursesw, main,  , [AC_MSG_ERROR([Couldn't find ncursesw library])] )
+	AC_SEARCH_LIBS(stdscr, tinfow,, [AC_MSG_ERROR([Cannot find a library providing stdscr])])
 	#AC_CHECK_LIB(ncurses++w, main,  , [AC_MSG_ERROR([Couldn't find ncurses++w library])] )
 	AC_CHECK_LIB(formw,    main,  , [AC_MSG_ERROR([Couldn't find formw library])] )
 	AC_CHECK_LIB(panelw,   main,  , [AC_MSG_ERROR([Couldn't find panelw library])] )