Fix libclc build

PR #1091 has refactor the logic of prepare_builtins into utils/CMakeLists.txt.
We don't need to duplicate logic in CMakeLists.txt now.

Before we upstream the utils/CMakeLists.txt, we should just remove the duplicate code.

Author: jsji

libclc/CMakeLists.txt

@@ -168,23 +168,6 @@ enable_language( CLC LLAsm )
 # Configure prepare_builtins
 add_subdirectory(utils)
 
-# This needs to be set before any target that needs it
-# We need to use LLVM_INCLUDE_DIRS here, because if we are linking to an
-# llvm build directory, this includes $src/llvm/include which is where all the
-# headers are not $build/include/ which is what LLVM_INCLUDE_DIR is set to.
-include_directories( ${LLVM_INCLUDE_DIRS} )
-
-# Setup prepare_builtins tools
-set(LLVM_LINK_COMPONENTS
-  BitReader
-  BitWriter
-  Core
-)
-add_llvm_executable( prepare_builtins utils/prepare-builtins.cpp )
-target_compile_definitions( prepare_builtins PRIVATE ${LLVM_VERSION_DEFINE} )
-# These were not properly reported in early LLVM and we don't need them
-target_compile_options( prepare_builtins PRIVATE -fno-rtti -fno-exceptions )
-
 # Setup arch devices
 set( r600--_devices cedar cypress barts cayman )
 set( amdgcn--_devices tahiti )