Avoid multiple definition warnings when both config.h and

llvm-config.h are included.

This is the cmake counterpart of r110547. See bug #7809.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110753 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Config/llvm-config.h.cmake

@@ -11,6 +11,11 @@
    they can be in exported headers and won't override package specific
    directives.  This is a C file so we can include it in the llvm-c headers.  */
 
+/* To avoid multiple inclusions of these variables when we include the exported
+   headers and config.h, conditionally include these.  */
+/* TODO: This is a bit of a hack.  */
+#ifndef CONFIG_H
+
 /* Installation directory for binary executables */
 #cmakedefine LLVM_BINDIR "${LLVM_BINDIR}"
 
@@ -82,3 +87,5 @@
 
 /* Installation prefix directory */
 #cmakedefine LLVM_PREFIX "${LLVM_PREFIX}"
+
+#endif