gl-renderer: move GL_EXT_texture_rg extension check

This is a GL extension and not EGL, so it should be checked after the
EGL context has been created.

Signed-off-by: Arnaud Vrac <avrac@freebox.fr>
Reviewed-by: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Daniel Stone <daniels@collabora.com>

libweston/gl-renderer.c

@@ -3221,9 +3221,6 @@ gl_renderer_setup_egl_extensions(struct weston_compositor *ec)
 		gr->has_dmabuf_import_modifiers = 1;
 	}
 
-	if (weston_check_egl_extension(extensions, "GL_EXT_texture_rg"))
-		gr->has_gl_texture_rg = 1;
-
 	if (weston_check_egl_extension(extensions, "EGL_KHR_fence_sync") &&
 	    weston_check_egl_extension(extensions, "EGL_ANDROID_native_fence_sync")) {
 		gr->create_sync =
@@ -3691,6 +3688,9 @@ gl_renderer_setup(struct weston_compositor *ec, EGLSurface egl_surface)
 	if (weston_check_egl_extension(extensions, "GL_EXT_unpack_subimage"))
 		gr->has_unpack_subimage = 1;
 
+	if (weston_check_egl_extension(extensions, "GL_EXT_texture_rg"))
+		gr->has_gl_texture_rg = 1;
+
 	if (weston_check_egl_extension(extensions, "GL_OES_EGL_image_external"))
 		gr->has_egl_image_external = 1;