Add EXT_separate_depth_stencil extension

Allows separate depth and stencil buffers to be attached to an FBO in
GLES3.
diff --git a/extensions/EXT/EXT_separate_depth_stencil.txt b/extensions/EXT/EXT_separate_depth_stencil.txt
new file mode 100644
index 0000000..e3f7c8d
--- /dev/null
+++ b/extensions/EXT/EXT_separate_depth_stencil.txt
@@ -0,0 +1,65 @@
+Name
+
+    EXT_separate_depth_stencil
+
+Name Strings
+
+    GL_EXT_separate_depth_stencil
+
+Contributors
+
+    Thomas Spurden
+
+Contact
+
+    Thomas Spurden, Broadcom (thomas.spurden 'at' broadcom.com)
+
+Status
+
+    TBD
+
+Version
+
+    Last Modified Date: 21/01/2022
+
+Number
+
+    OpenGL ES Extension #???
+
+Dependencies
+
+    The extension is written against the OpenGL ES 3.0.6 (November 1, 2019)
+    standard
+
+Overview
+
+    This extension adds support for binding a different image to the depth and
+    stencil attachments of a framebuffer object.
+
+New Types
+
+    None
+
+New Procedures and Functions
+
+   None
+
+New Tokens
+
+   None
+
+Additions to Chapter 4 of the OpenGL ES 3.0 Specification (Per-Fragment Operations and the
+Framebuffer)
+
+   Modify section 4.4.4.2 (Whole Framebuffer Completeness)
+
+   Delete the whole of the 4th bullet point "Depth and stencil attachments, if
+   present, are the same image..."
+
+Issues
+
+Revision History
+    #2   (March 3, 2022) Thomas Spurden
+         - Changed to EXT from BRCM
+    #1   (January 21, 2022) Thomas Spurden
+         - Initial draft
diff --git a/xml/gl.xml b/xml/gl.xml
index 995b90d..06af90e 100644
--- a/xml/gl.xml
+++ b/xml/gl.xml
@@ -41464,6 +41464,7 @@
                 <command name="glSecondaryColorPointerEXT"/>
             </require>
         </extension>
+        <extension name="GL_EXT_separate_depth_stencil" supported="gles2"/>
         <extension name="GL_EXT_separate_shader_objects" supported="gl|glcore|gles2">
             <require api="gl" comment="The OpenGL version of this extension is completely unrelated to the OpenGL ES version">
                 <enum name="GL_ACTIVE_PROGRAM_EXT"/>