crypto/rsa: fix URL for the PKCS #1 v2.2 document in pss.go

The PKCS #1 v2.2 document has been moved to an EMC
website with a new URL. This CL updates the reference to the document to
the new URL.

The new URL is referenced under https://en.wikipedia.org/wiki/PKCS_1

Fixes #21642

Change-Id: Ib8738b0c4c3bb9ec427bebea20c4aacd607ba0db
Reviewed-on: https://go-review.googlesource.com/59351Reviewed-by: Emmanuel Odeke <emm.odeke@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

src/crypto/rsa/pss.go

@@ -6,7 +6,7 @@ package rsa
 
 // This file implements the PSS signature scheme [1].
 //
-// [1] http://www.rsa.com/rsalabs/pkcs/files/h11300-wp-pkcs-1v2-2-rsa-cryptography-standard.pdf
+// [1] https://www.emc.com/collateral/white-papers/h11300-pkcs-1v2-2-rsa-cryptography-standard-wp.pdf
 
 import (
 	"bytes"