meson: don't build libGLES*.so with GLVND

GLVND already provides these, so distro packagers have been deleting
them all along. Let's save ourselves the trouble and not build them in
the first place.
Signed-off-by: Eric Engestrom <eric.engestrom@intel.com>
Reviewed-by: Matt Turner <mattst88@gmail.com>
Reviewed-by: Dylan Baker <dylan@pnwbakers.com>
Reviewed-by: Emil Velikov <emil.velikov@collabora.com>

src/mapi/meson.build

@@ -33,9 +33,11 @@ subdir('glapi')
 if with_shared_glapi
   subdir('shared-glapi')
 endif
-if with_gles1
-  subdir('es1api')
-endif
-if with_gles2
-  subdir('es2api')
+if not with_glvnd
+  if with_gles1
+    subdir('es1api')
+  endif
+  if with_gles2
+    subdir('es2api')
+  endif
 endif