mesa/es: Merge back to core mesa.

With the omit list gone, there are not too many differences in building
core mesa and ES overlay.  Remove the mesa/es and build both of them in
src/mesa/Makefile.
diff --git a/docs/opengles.html b/docs/opengles.html
index 9984a79..63cc114 100644
--- a/docs/opengles.html
+++ b/docs/opengles.html
@@ -51,10 +51,10 @@
 
 <table border="1" style="text-align: center;">
 	<tr><td>Library Name</td><td>Used By</td><td>Enabled</td><td>OpenGL</td><td>OpenGL ES 1.x</td><td>OpenGL ES 2.x</td></tr>
-	<tr><td><code>src/mesa/libmesa.a</td><td>Classic DRI drivers</td><td>y</td><td>y</td><td>--enable-gles1</td><td>--enable-gles2</td></tr>
-	<tr><td><code>src/mesa/libmesagallium.a</td><td>Gallium EGL and DRI drivers</td><td>y</td><td>y</td><td>--enable-gles1</td><td>--enable-gles2</td></tr>
-	<tr><td><code>src/mesa/es/libes1gallium.a</td><td>Gallium EGL drivers</td><td>--enable-gles-overlay</td><td>n</td><td>y</td><td>n</td></tr>
-	<tr><td><code>src/mesa/es/libes2gallium.a</td><td>Gallium EGL drivers</td><td>--enable-gles-overlay</td><td>n</td><td>n</td><td>y</td></tr>
+	<tr><td><code>libmesa.a</td><td>Classic DRI drivers</td><td>y</td><td>y</td><td>--enable-gles1</td><td>--enable-gles2</td></tr>
+	<tr><td><code>libmesagallium.a</td><td>Gallium EGL and DRI drivers</td><td>y</td><td>y</td><td>--enable-gles1</td><td>--enable-gles2</td></tr>
+	<tr><td><code>libes1gallium.a</td><td>Gallium EGL drivers</td><td>--enable-gles-overlay</td><td>n</td><td>y</td><td>n</td></tr>
+	<tr><td><code>libes2gallium.a</td><td>Gallium EGL drivers</td><td>--enable-gles-overlay</td><td>n</td><td>n</td><td>y</td></tr>
 </table>
 
 <h3>Dispatch Table</h3>