Rename CMake variable; this fell out of r189127 somehow.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@189129 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 386f3e7..b975c0e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -48,8 +48,8 @@
   include_directories("${PATH_TO_LLVM_BUILD}/include" "${LLVM_MAIN_INCLUDE_DIR}")
   link_directories("${PATH_TO_LLVM_BUILD}/lib")
 
-  exec_program("${PATH_TO_LLVM_CONFIG} --bindir" OUTPUT_VARIABLE LLVM_TABLEGEN_EXE)
-  set(LLVM_TABLEGEN_EXE "${LLVM_TABLEGEN_EXE}/llvm-tblgen${CMAKE_EXECUTABLE_SUFFIX}")
+  exec_program("${PATH_TO_LLVM_CONFIG} --bindir" OUTPUT_VARIABLE LLVM_BINARY_DIR)
+  set(LLVM_TABLEGEN_EXE "${LLVM_BINARY_DIR}/llvm-tblgen${CMAKE_EXECUTABLE_SUFFIX}")
 
   # Define the default arguments to use with 'lit', and an option for the user
   # to override.