Revert "Revert "Windows: Add support for unicode command lines""

This reverts commit r192070 which reverted r192069, I forgot to
regenerate the configure scripts.

llvm-svn: 192079
diff --git a/llvm/lib/Support/Windows/Signals.inc b/llvm/lib/Support/Windows/Signals.inc
index bce83b9..2b4a66d 100644
--- a/llvm/lib/Support/Windows/Signals.inc
+++ b/llvm/lib/Support/Windows/Signals.inc
@@ -135,7 +135,7 @@
 static fpSymFunctionTableAccess64 SymFunctionTableAccess64;
 
 static bool load64BitDebugHelp(void) {
-  HMODULE hLib = ::LoadLibrary("Dbghelp.dll");
+  HMODULE hLib = ::LoadLibrary(TEXT("Dbghelp.dll"));
   if (hLib) {
     StackWalk64 = (fpStackWalk64)
                       ::GetProcAddress(hLib, "StackWalk64");