cmd/go, cmd/link: use "Go" not "GO" as ELF note identifier

Change-Id: I038e892725836ab7718f7638e8ad5712953f2cb5
Reviewed-on: https://go-review.googlesource.com/10704
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/misc/cgo/testshared/shared_test.go b/misc/cgo/testshared/shared_test.go
index f7a99af..09b159d 100644
--- a/misc/cgo/testshared/shared_test.go
+++ b/misc/cgo/testshared/shared_test.go
@@ -399,7 +399,7 @@
 	abiHashNoteFound := false
 	depsNoteFound := false
 	for _, note := range notes {
-		if note.name != "GO\x00\x00" {
+		if note.name != "Go\x00\x00" {
 			continue
 		}
 		switch note.tag {