cmd/link: disable internal PIE for now

There's more work to do.

Updates golang#17068

Change-Id: I4e16c0e8e9ac739e1fe266224c3769f6c5b2e070
Reviewed-on: https://go-review.googlesource.com/29076
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: David Crawshaw <crawshaw@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/link/internal/ld/lib.go

@@ -455,7 +455,7 @@ func (ctxt *Link) loadlib() {
 
 		// Force external linking for PIE binaries on systems
 		// that do not support internal PIE linking.
-		if Buildmode == BuildmodePIE && (obj.GOOS != "linux" || SysArch.Family != sys.AMD64) {
+		if Buildmode == BuildmodePIE {
 			Linkmode = LinkExternal
 		}