Changes for building Clang and others using LLVM as an external
library.

Installs tblgen (required by Clang).

Translates handling of user settings and platform-dependant options to
its own file, where it can included by another project.

Installs the .cmake files required by projects like Clang.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124816 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/cmake/modules/TableGen.cmake b/cmake/modules/TableGen.cmake
index c1a11b3..7383119 100644
--- a/cmake/modules/TableGen.cmake
+++ b/cmake/modules/TableGen.cmake
@@ -21,7 +21,8 @@
     # The file in LLVM_TARGET_DEFINITIONS may be not in the current
     # directory and local_tds may not contain it, so we must
     # explicitly list it here:
-    DEPENDS tblgen ${local_tds} ${global_tds} ${LLVM_TARGET_DEFINITIONS_ABSOLUTE}
+    DEPENDS ${LLVM_TABLEGEN_EXE} ${local_tds} ${global_tds}
+    ${LLVM_TARGET_DEFINITIONS_ABSOLUTE}
     COMMENT "Building ${ofn}..."
     )
   add_custom_command(OUTPUT ${CMAKE_CURRENT_BINARY_DIR}/${ofn}