!12 Add toolchain_clang build support

From: @liyunfei33 
Reviewed-by: @cf-zhao 
Signed-off-by: @cf-zhao

openmp.spec

@@ -1,5 +1,10 @@
 %bcond_without sys_llvm
 %bcond_with check
+%bcond_without toolchain_clang
+
+%if %{with toolchain_clang}
+%global toolchain clang
+%endif
 
 %global toolchain clang
 
@@ -32,7 +37,7 @@
 
 Name:    %{pkg_name}
 Version: %{openmp_version}
-Release: 1
+Release: 2
 Summary: OpenMP runtime for clang
 
 License: Apache License 2.0
@@ -93,6 +98,10 @@ OpenMP header files.
 	-DOPENMP_LIBDIR_SUFFIX=64 \
 %else
 	-DOPENMP_LIBDIR_SUFFIX= \
+%endif
+%if "%{toolchain}" == "clang"
+	-DCMAKE_C_COMPILER=clang \
+	-DCMAKE_CXX_COMPILER=clang++ \
 %endif
 	-DCMAKE_SKIP_RPATH:BOOL=ON
 
@@ -139,6 +148,9 @@ rm -rf %{buildroot}%{install_libdir}/libarcher_static.a
 %{install_libdir}/libomptarget.so
  
 %changelog
+* Fri Jul 5 2024 liyunfei <liyunfei33@huawei.com> - 17.0.6-2
+- Add toolchain_clang build support
+
 * Mon Dec 4 2023 zhoujing <zhoujing106@huawei.com> - 17.0.6-1
 - Update to 17.0.6