docs: Update TODOs of egl.html.
Thread-safety is no longer a TODO item. There are surely bugs to be
fixed though.
diff --git a/docs/egl.html b/docs/egl.html
index 844cc32..82cc066 100644
--- a/docs/egl.html
+++ b/docs/egl.html
@@ -302,10 +302,18 @@
client API renders to the specified render buffer for pixmap and pbuffer
surfaces.</p>
+<h3><code>EGLDisplay</code> Mutex</h3>
+
+The <code>EGLDisplay</code> will be locked before calling any of the dispatch
+functions (well, except for GetProcAddress which does not take an
+<code>EGLDisplay</code>). This guarantees that the same dispatch function will
+not be called with the sample display at the same time. If a driver has access
+to an <code>EGLDisplay</code> without going through the EGL APIs, the driver
+should as well lock the display before using it.
+
<h3>TODOs</h3>
<ul>
-<li>Thread safety</li>
<li>Pass the conformance tests</li>
<li>Better automatic driver selection: <code>EGL_DISPLAY</code> loads all
drivers and might eat too much memory.</li>