title: How to add header file path in CMake file
body: <p>I am new to OpenCL. I have written a vector addition code in OpenCL with help from Internet. I have included one header file i.e. <code>CL/cl.h</code> using <code>#include</code>.</p>
  
  <p>I am using NVIDIA graphic card and the OpenCL implementation is NVIDIA_GPU_Computing_SDK. My OpenCL header files are residing at this path <code>/opt/NVIDIA_GPU_Computing_SDK/OpenCL/common/inc</code>. I can run OpenCL programs through linux terminal by adding this path when compiling my code. But now I want to write CMake file for this code. CMake files are working fine for C programs, but not OpenCL programs because of this Path problem. In terminal, I used to enter <code>$cmake .</code>, after this <code>$make</code>, it will search for a Makefile which is created by cmake, now my error is  after entering command <code>make</code></p>
  
  <pre><code>fatal error: CL/cl.h: No such file or directory!
  </code></pre>
  
  <p>Now tell me how can I include this header file into CMake file?</p>