CMake: use add_llvm_example for HowToUseJIT.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57944 91177308-0d34-0410-b5e6-96231b3b80d8

examples/HowToUseJIT/CMakeLists.txt

@@ -1,5 +1,5 @@
 set(LLVM_LINK_COMPONENTS jit interpreter nativecodegen)
 
-add_llvm_executable(HowToUseJIT
+add_llvm_example(HowToUseJIT
   HowToUseJIT.cpp
   )