Wayland: Fix glfwInit closing stdin on failure

If platform initialization failed before either timer fd member had been
set to -1 or a valid fd, termination would close stdin.

(cherry picked from commit 3bbb41eacc)

README.md

@@ -161,6 +161,7 @@ information on what to include when reporting a bug.
  - [Wayland] Bugfix: `glfwSetWindowSize` would resize a full screen window
  - [Wayland] Bugfix: A window content scale event would be emitted every time
    the window resized
+ - [Wayland] Bugfix: If `glfwInit` failed it would close stdin
 
 
 ## Contact

src/wl_init.c

@@ -314,6 +314,10 @@ int _glfwPlatformInit(void)
     long cursorSizeLong;
     int cursorSize;
 
+    // These must be set before any failure checks
+    _glfw.wl.timerfd = -1;
+    _glfw.wl.cursorTimerfd = -1;
+
     _glfw.wl.cursor.handle = _glfw_dlopen("libwayland-cursor.so.0");
     if (!_glfw.wl.cursor.handle)
     {
@@ -430,7 +434,6 @@ int _glfwPlatformInit(void)
 
     _glfwInitTimerPOSIX();
 
-    _glfw.wl.timerfd = -1;
     if (_glfw.wl.seatVersion >= 4)
         _glfw.wl.timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_CLOEXEC | TFD_NONBLOCK);