Stereo3D: Don't rely on GetEFBLayers() when dealing with shaders.

Shaders may be compiled before the FramebufferManager is initialized.
VideoConfigDiag: Remove double space.
VideoConfig: Fix convergence parameter.

Looks like a rebase failed somewhere.
Merge pull request #1786 from Armada651/stereo-fixes

Stereo3D: Don't rely on GetEFBLayers() when dealing with shaders.