Make sure -Wnon-virtual-dtor is passed only when compiling with Clang

Another follow-up for #92953. Addresses buildbot failure https://lab.llvm.org/buildbot/#/builders/193/builds/52421

Author: Endilll

llvm/cmake/modules/HandleLLVMOptions.cmake

@@ -856,7 +856,9 @@ if (LLVM_ENABLE_WARNINGS AND (LLVM_COMPILER_IS_GCC_COMPATIBLE OR CLANG_CL))
   # The LLVM libraries have no stable C++ API, so -Wnoexcept-type is not useful.
   append("-Wno-noexcept-type" CMAKE_CXX_FLAGS)
 
-  append("-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
+  if (CMAKE_CXX_COMPILER_ID MATCHES "Clang")
+    append("-Wnon-virtual-dtor" CMAKE_CXX_FLAGS)
+  endif()
   append("-Wdelete-non-virtual-dtor" CMAKE_CXX_FLAGS)
 
   # Enable -Wsuggest-override if it's available, and only if it doesn't