runtime: fix URL in a comment

For various reasons Intel has suspended viewing web pages in the .ru
domain, so change the domain of the documents cited in the code
to the .com domain. In addition, the chapter numbers in the document
were updated and fix it.

Change-Id: I718be1548ec46f05ebc4f73873d4635c1d5fc76d
Reviewed-on: https://go-review.googlesource.com/c/go/+/399060
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Emmanuel Odeke <emmanuel@orijtech.com>
Auto-Submit: Emmanuel Odeke <emmanuel@orijtech.com>

Author: cia-rana

src/runtime/memmove_amd64.s

@@ -418,9 +418,9 @@ gobble_mem_fwd_loop:
 	PREFETCHNTA 0x1C0(SI)
 	PREFETCHNTA 0x280(SI)
 	// Prefetch values were chosen empirically.
-	// Approach for prefetch usage as in 7.6.6 of [1]
+	// Approach for prefetch usage as in 9.5.6 of [1]
 	// [1] 64-ia-32-architectures-optimization-manual.pdf
-	// https://www.intel.ru/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
+	// https://www.intel.com/content/dam/www/public/us/en/documents/manuals/64-ia-32-architectures-optimization-manual.pdf
 	VMOVDQU	(SI), Y0
 	VMOVDQU	0x20(SI), Y1
 	VMOVDQU	0x40(SI), Y2