Delete bundled copy of NSS and replace with README.

nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c

Index: nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c
diff --git a/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c b/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c
deleted file mode 100644
index 2631aed0310aa1d1906dc4f07aed6d3b5305a9d2..0000000000000000000000000000000000000000
--- a/nss/lib/libpkix/pkix_pl_nss/system/pkix_pl_error.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/* This Source Code Form is subject to the terms of the Mozilla Public
- * License, v. 2.0. If a copy of the MPL was not distributed with this
- * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
-/*
- * pkix_pl_error.c
- *
- * PL error functions
- *
- */
-
-#include "pkix_pl_common.h"
-
-#undef PKIX_ERRORENTRY
-
-#define PKIX_ERRORENTRY(name,desc,plerr) plerr
-
-const PKIX_Int32 PKIX_PLErrorIndex[] =
-{
-#include "pkix_errorstrings.h"
-};
-
-int
-PKIX_PL_GetPLErrorCode()
-{
-    return PORT_GetError();
-}