windisplay: Remove unused config.prc variable definitions:

- responsive-minimized-fullscreen-window
- hold-keys-across-windows
- swapbuffer-framelock

panda/src/windisplay/config_windisplay.cxx

@@ -27,17 +27,6 @@ ConfigureFn(config_windisplay) {
   init_libwindisplay();
 }
 
-ConfigVariableBool responsive_minimized_fullscreen_window
-("responsive-minimized-fullscreen-window",false);
-
-ConfigVariableBool hold_keys_across_windows
-("hold-keys-across-windows", false,
- PRC_DESC("Set this true to remember the current state of the keyboard while "
-          "the window focus is lost, or false to pretend the user is not "
-          "holding down any keys while the window focus is lost.  In either "
-          "case it should accurately restore the correct keyboard state when "
-          "the window focus is regained."));
-
 ConfigVariableBool do_vidmemsize_check
 ("do-vidmemsize-check", true,
  PRC_DESC("if true, use ddraw's GetAvailVidMem to fail if driver says "
@@ -76,10 +65,6 @@ ConfigVariableBool dpi_window_resize
           "panel.  Only available in Windows 8.1 and later, and requires "
           "dpi-aware to be set as well."));
 
-ConfigVariableBool swapbuffer_framelock
-("swapbuffer-framelock", false,
- PRC_DESC("Set this true to enable HW swapbuffer frame-lock on 3dlabs cards"));
-
 ConfigVariableBool paste_emit_keystrokes
 ("paste-emit-keystrokes", true,
  PRC_DESC("Handle paste events (Ctrl-V) as separate keystroke events for each "

panda/src/windisplay/config_windisplay.h

@@ -21,8 +21,6 @@
 
 NotifyCategoryDecl(windisplay, EXPCL_PANDAWIN, EXPTP_PANDAWIN);
 
-extern ConfigVariableBool responsive_minimized_fullscreen_window;
-extern ConfigVariableBool hold_keys_across_windows;
 extern ConfigVariableBool do_vidmemsize_check;
 extern ConfigVariableBool auto_cpu_data;
 extern ConfigVariableBool ime_hide;
@@ -32,8 +30,6 @@ extern ConfigVariableBool dpi_window_resize;
 extern ConfigVariableBool paste_emit_keystrokes;
 extern ConfigVariableBool disable_message_loop;
 
-extern EXPCL_PANDAWIN ConfigVariableBool swapbuffer_framelock;
-
 extern EXPCL_PANDAWIN void init_libwindisplay();
 
 #endif