display: ensure that cursor is visible when compiled with --with-slang

This fixes https://savannah.gnu.org/bugs/?52651

.
Reported-by: David Lawrence Ramsey <pooka109@gmail.com>

src/nano.c

@@ -557,6 +557,7 @@ void finish(void)
     blank_statusbar();
     blank_bottombars();
     wrefresh(bottomwin);
+    curs_set(1);
     endwin();
 
     /* Restore the old terminal settings. */
@@ -584,6 +585,7 @@ void die(const char *msg, ...)
 {
     va_list ap;
 
+    curs_set(1);
     endwin();
 
     /* Restore the old terminal settings. */

src/winio.c

@@ -185,8 +185,12 @@ void get_key_buffer(WINDOW *win)
      * screen updates. */
     doupdate();
 
-    if (reveal_cursor)
+    if (reveal_cursor) {
 	curs_set(1);
+#ifdef USE_SLANG
+	doupdate();
+#endif
+    }
 
     /* Read in the first keystroke using whatever mode we're in. */
     while (input == ERR) {