Added OpenCL library to linker flags when building OpenCL backend
Added OpenCL library to linker flags when building OpenCL backend

botev/arrayfire-rust,arrayfire/arrayfire-rust,9prady9/arrayfire-rust,tedsta/arrayfire-rust,pavanky/arrayfire-rust,9prady9/arrayfire-rust,9prady9/arrayfire-rust,arrayfire/arrayfire_rust,9prady9/arrayfire-rust,arrayfire/arrayfire-rust,jramapuram/arrayfire_rust,arrayfire/arrayfire-rust