Fix compilation problem with Qt3D when using OpenGL ES 2 backend.

In commit ef33536447b52f71346e615e5aa37e5dee56140a bindUniform was
introduced but with a minor copy/paste bug for OpenGL ES backend. This
patch fix that compilation problem.

Change-Id: I0b4828a101b00f2939f99f26182162d0430d7898
Reviewed-by: Paul Lemire <paul.lemire@kdab.com>