[cogl] build: don't referencing wayland syms if not available

[Robert Bragg <rbragg src gnome org>]

commit 1527b017c51d5c91cec117f626a916ffbd3ae570
Author: Robert Bragg <robert linux intel com>
Date:   Wed Jul 13 12:42:22 2011 +0100

    build: don't referencing wayland syms if not available
    
    cogl-winsys-egl-feature-functions.h was unconditionally depending on the
    struct wl_display type being defined. This guards the check for the
    "WL_bind_wayland_display" extension with
     #ifdef COGL_HAS_EGL_PLATFORM_WAYLAND_SUPPORT
    
    Signed-off-by: Neil Roberts <neil linux intel com>

 cogl/winsys/cogl-winsys-egl-feature-functions.h |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)
---
diff --git a/cogl/winsys/cogl-winsys-egl-feature-functions.h b/cogl/winsys/cogl-winsys-egl-feature-functions.h
index 7967563..0bc50b6 100644
--- a/cogl/winsys/cogl-winsys-egl-feature-functions.h
+++ b/cogl/winsys/cogl-winsys-egl-feature-functions.h
@@ -73,6 +73,7 @@ COGL_WINSYS_FEATURE_BEGIN (image_pixmap,
                            "image_pixmap\0",
                            COGL_EGL_WINSYS_FEATURE_EGL_IMAGE_FROM_X11_PIXMAP)
 COGL_WINSYS_FEATURE_END ()
+#ifdef COGL_HAS_EGL_PLATFORM_WAYLAND_SUPPORT
 COGL_WINSYS_FEATURE_BEGIN (bind_wayland_display,
                            "WL\0",
                            "bind_wayland_display\0",
@@ -84,3 +85,4 @@ COGL_WINSYS_FEATURE_FUNCTION (EGLBoolean, eglUnbindWaylandDisplay,
                               (EGLDisplay dpy,
                                struct wl_display *wayland_display))
 COGL_WINSYS_FEATURE_END ()
+#endif