Make a function file-scoped.

llvm-svn: 266816
diff --git a/lld/ELF/LinkerScript.cpp b/lld/ELF/LinkerScript.cpp
index bd239d4..9a47ee6 100644
--- a/lld/ELF/LinkerScript.cpp
+++ b/lld/ELF/LinkerScript.cpp
@@ -138,7 +138,7 @@
 }
 
 // Evaluates the expression given by list of tokens.
-uint64_t evaluate(ArrayRef<StringRef> Tokens, uint64_t Dot) {
+static uint64_t evaluate(ArrayRef<StringRef> Tokens, uint64_t Dot) {
   uint64_t V = parsePrimary(Tokens, Dot);
   V = parseExpr(V, 0, Tokens, Dot);
   if (!Tokens.empty())