add find_package call for OpenCL

Author: AD2605

ggml/src/ggml-sycl/CMakeLists.txt

@@ -51,6 +51,9 @@ target_compile_options(ggml-sycl PRIVATE "-Wno-narrowing")
 # Link against oneDNN
 set(GGML_SYCL_DNNL 0)
 if(GGML_SYCL_DNN)
+    if (CMAKE_CXX_COMPILER_ID STREQUAL "Clang")
+           find_package(OpenCL REQUIRED)
+    endif()
     find_package(DNNL)
     if(DNNL_FOUND)
         if (NOT DEFINED DNNL_GPU_VENDOR)