llvm-lib: Implement /list flag

Differential Revision: https://reviews.llvm.org/D57952

llvm-svn: 353620
diff --git a/llvm/lib/ToolDrivers/llvm-lib/Options.td b/llvm/lib/ToolDrivers/llvm-lib/Options.td
index dd41952..4c297f7 100644
--- a/llvm/lib/ToolDrivers/llvm-lib/Options.td
+++ b/llvm/lib/ToolDrivers/llvm-lib/Options.td
@@ -10,6 +10,9 @@
       Joined<["/", "-", "-?"], name#":">, HelpText<help>;
 
 def libpath: P<"libpath", "Object file search path">;
+
+// Can't be called "list" since that's a keyword.
+def lst    : F<"list">, HelpText<"List contents of .lib file on stdout">;
 def out    : P<"out", "Path to file to write output">;
 
 def llvmlibthin : F<"llvmlibthin">,