go 1.11: Switch to GO 1.11

Minimal amount of changes needed to switch to GO 1.11
* crypto/internal/cipherhw was removed and internal/cpu was introduced
* wrong code formatting in handhsake_server_test.go was breaking
  the build

.travis.yml

@@ -5,7 +5,7 @@ services:
   - docker
 
 go:
-  - 1.10.x
+  - 1.11.x
 
 env:
   - TEST_SUITE=test-unit

_dev/bogo/Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.10-alpine
+FROM golang:1.11-alpine
 
 RUN apk add --update \
     git \

common.go

@@ -7,12 +7,12 @@ package tls
 import (
 	"container/list"
 	"crypto"
-	"crypto/internal/cipherhw"
 	"crypto/rand"
 	"crypto/sha512"
 	"crypto/x509"
 	"errors"
 	"fmt"
+	"internal/cpu"
 	"io"
 	"math/big"
 	"net"
@@ -1127,7 +1127,19 @@ func defaultTLS13CipherSuites() []uint16 {
 
 func initDefaultCipherSuites() {
 	var topCipherSuites, topTLS13CipherSuites []uint16
-	if cipherhw.AESGCMSupport() {
+
+	// Check the cpu flags for each platform that has optimized GCM implementations.
+	// Worst case, these variables will just all be false
+	hasGCMAsmAMD64 := cpu.X86.HasAES && cpu.X86.HasPCLMULQDQ
+
+	hasGCMAsmARM64 := cpu.ARM64.HasAES && cpu.ARM64.HasPMULL
+
+	// Keep in sync with crypto/aes/cipher_s390x.go.
+	hasGCMAsmS390X := cpu.S390X.HasAES && cpu.S390X.HasAESCBC && cpu.S390X.HasAESCTR && (cpu.S390X.HasGHASH || cpu.S390X.HasAESGCM)
+
+	hasGCMAsm := hasGCMAsmAMD64 || hasGCMAsmARM64 || hasGCMAsmS390X
+
+	if hasGCMAsm {
 		// If AES-GCM hardware is provided then prioritise AES-GCM
 		// cipher suites.
 		topTLS13CipherSuites = []uint16{