free up some console alloc()'d memory under curses

tty takes care of this, but it wasn't being done under curses

include/extern.h

@@ -2182,7 +2182,7 @@ extern void synch_cursor(void);
 extern void nethack_enter_consoletty(void);
 extern int get_console_width(void);
 extern int get_console_height(void);
-extern void consoletty_exit(void);
+extern void console_exit(void);
 extern int set_keyhandling_via_option(void);
 #ifdef ENHANCED_SYMBOLS
 extern void tty_utf8graphics_fixup(void);

sys/windows/consoletty.c

@@ -954,7 +954,7 @@ tty_number_pad(int state UNUSED)
 void
 term_shutdown(void)
 {
-    consoletty_exit();
+    console_exit();
 }
 
 #ifdef ASCIIGRAPH
@@ -1044,14 +1044,19 @@ consoletty_open(int mode UNUSED)
 extern void set_emergency_io(void);
 
 void
-consoletty_exit(void)
+console_exit(void)
 {
     free_custom_colors();
-    free((genericptr_t) console.front_buffer);
-    free((genericptr_t) console.back_buffer);
+    if (console.front_buffer)
+        free((genericptr_t) console.front_buffer);
+    if (console.back_buffer)
+        free((genericptr_t) console.back_buffer);
     console.front_buffer = console.back_buffer = 0;
-    free((genericptr_t) console.localestr);
-    free((genericptr_t) console.orig_localestr);
+    if (console.localestr)
+        free((genericptr_t) console.localestr), console.localestr = 0;
+    if (console.orig_localestr)
+        free((genericptr_t) console.orig_localestr),
+            console.orig_localestr = 0;
     set_emergency_io();
 }
 

sys/windows/windsys.c

@@ -526,6 +526,13 @@ nethack_exit(int code)
     genl_status_finish();
 #ifdef MSWIN_GRAPHICS
     free_winmain_stuff();
+#endif
+#ifdef WIN32CON
+#ifdef CURSES_GRAPHICS
+    if (WINDOWPORT(curses)) {
+        console_exit();
+    }
+#endif
 #endif
     exit(code);
 }