cmd/go: set correct install location for cmd/compile and cmd/link

Without this, they install to $GOROOT/bin.

Change-Id: Iae4b8f59c8392f6abd841490e56922738089f8d4
Reviewed-on: https://go-review.googlesource.com/10297Reviewed-by: Russ Cox <rsc@golang.org>

src/cmd/go/pkg.go

@@ -394,24 +394,16 @@ const (
 
 // goTools is a map of Go program import path to install target directory.
 var goTools = map[string]targetDir{
-	"cmd/5g":                               toTool,
-	"cmd/5l":                               toTool,
-	"cmd/6g":                               toTool,
-	"cmd/6l":                               toTool,
-	"cmd/7g":                               toTool,
-	"cmd/7l":                               toTool,
-	"cmd/8g":                               toTool,
-	"cmd/8l":                               toTool,
-	"cmd/9g":                               toTool,
-	"cmd/9l":                               toTool,
 	"cmd/addr2line":                        toTool,
 	"cmd/api":                              toTool,
 	"cmd/asm":                              toTool,
+	"cmd/compile":                          toTool,
 	"cmd/cgo":                              toTool,
 	"cmd/cover":                            toTool,
 	"cmd/dist":                             toTool,
 	"cmd/doc":                              toTool,
 	"cmd/fix":                              toTool,
+	"cmd/link":                             toTool,
 	"cmd/newlink":                          toTool,
 	"cmd/nm":                               toTool,
 	"cmd/objdump":                          toTool,