Add 'const' qualifiers to static const char* variables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186371 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Object/Archive.cpp b/lib/Object/Archive.cpp
index 719d104..c6cf219 100644
--- a/lib/Object/Archive.cpp
+++ b/lib/Object/Archive.cpp
@@ -21,7 +21,7 @@
 using namespace llvm;
 using namespace object;
 
-static const char *Magic = "!<arch>\n";
+static const char *const Magic = "!<arch>\n";
 
 void Archive::anchor() { }