Set API dispatch pointers for OES_EGL_image functions

This chunk fell through the cracks when I rebase the EGLImage patch series.

src/mesa/main/api_exec.c

@@ -753,4 +753,9 @@ _mesa_init_exec_table(struct _glapi_table *exec)
    /* GL_NV_conditional_render */
    SET_BeginConditionalRenderNV(exec, _mesa_BeginConditionalRender);
    SET_EndConditionalRenderNV(exec, _mesa_EndConditionalRender);
+
+#if FEATURE_OES_EGL_image
+   SET_EGLImageTargetTexture2DOES(exec, _mesa_EGLImageTargetTexture2DOES);
+   SET_EGLImageTargetRenderbufferStorageOES(exec, _mesa_EGLImageTargetRenderbufferStorageOES);
+#endif
 }