Build fails with ENABLE_HLSL=OFF

[fabmax]

I tried to build glslc without HLSL support but the final executables don't consider the ENABLE_HLSL option and instead always want to link the HLSL libs.

I'm compiling with emscripten to wasm and trying to reduce the size of the final assembly (currently it's 3.3MB). Not sure if excluding HLSL will yield much but I guess it's worth a try.

[zoddicus]

@dneto0 can you take a look at this?

[edvn0]

Up! On MacOS for me.