Enable PACKAGE_VERSION in cmake builds, this unbreaks the clang build with cmake.
Patch by Piotr Rak!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63213 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 2072c70..3dcc5e4 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -2,7 +2,8 @@
 cmake_minimum_required(VERSION 2.6.1)
 
 set(PACKAGE_NAME llvm)
-set(PACKAGE_VERSION svn)
+set(PACKAGE_VERSION 2.6svn)
+set(PACKAGE_STRING "${PACKAGE_NAME} ${PACKAGE_VERSION}")
 set(PACKAGE_BUGREPORT "llvmbugs@cs.uiuc.edu")
 
 if( CMAKE_SOURCE_DIR STREQUAL CMAKE_BINARY_DIR AND NOT MSVC_IDE )