D3D11: Use appropriate shader for PEEK_Z.

Trying to use GetDepthMatrixProgram outside of
TCacheEntry::FromRenderTarget is a bad idea, so don't.  Instead, use a
shader which only copies the input.

Fixes lens flare depth test in Twilight Princess. See
http://code.google.com/p/dolphin-emu/issues/detail?id=5999 .

Source/Core/VideoBackends/D3D/Render.cpp

@@ -391,7 +391,7 @@ u32 Renderer::AccessEFB(EFBAccessType type, u32 x, u32 y, u32 poke_data)
 								&RectToLock,
 								Renderer::GetTargetWidth(),
 								Renderer::GetTargetHeight(),
-								PixelShaderCache::GetDepthMatrixProgram(true),
+								PixelShaderCache::GetColorCopyProgram(true),
 								VertexShaderCache::GetSimpleVertexShader(),
 								VertexShaderCache::GetSimpleInputLayout());