Turn on fboRenderMipmap for D3D11 Bug: 1023747 Change-Id: I8ca320432aad663e2a6d70f494692df518376258 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1947710 Reviewed-by: Geoff Lang <geofflang@chromium.org> Commit-Queue: Shrek Shao <shrekshao@google.com>