OpenEXR has some dependecies that other other modules in Blender requires. When disabling OpenEXR these dependecies could not match and building blender would fail. This PR disables the next options when `WITH_IMAGE_OPENEXR=Off` - `WITH_OPENVDB` - `WITH_ALEMBIC` - `WITH_VULKAN_BACKEND` - `WITH_CYCLES_OSL` Additionally windows stores the IMath libraries in `IMATH_LIBRARIES` Linux and Mac stored the IMath libraries in `IMATH_LIBRARY`. This change will also adds `IMATH_LIBRARIES` variable to all platforms. Pull Request: blender/blender#106209