runtime internal/cpu: rename "Zeus" "NeoverseV1".

Rename "Zeus" to "NeoverseV1" for the partnum 0xd40 to be
consistent with the documentation of MIDR_EL1 as described in
https://developer.arm.com/documentation/101427/0101/?lang=en

Change-Id: I2e3d5ec76b953a831cb4ab0438bc1c403648644b
Reviewed-on: https://go-review.googlesource.com/c/go/+/414775
Reviewed-by: Jonathan Swinney <jswinney@amazon.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Eric Fang <eric.fang@arm.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>
Reviewed-by: Michael Pratt <mpratt@google.com>

src/internal/cpu/cpu.go

@@ -67,7 +67,7 @@ var ARM64 struct {
 	HasATOMICS   bool
 	HasCPUID     bool
 	IsNeoverseN1 bool
-	IsZeus       bool
+	IsNeoverseV1 bool
 	_            CacheLinePad
 }
 

src/internal/cpu/cpu_arm64.go

@@ -20,7 +20,7 @@ func doinit() {
 		{Name: "atomics", Feature: &ARM64.HasATOMICS},
 		{Name: "cpuid", Feature: &ARM64.HasCPUID},
 		{Name: "isNeoverseN1", Feature: &ARM64.IsNeoverseN1},
-		{Name: "isZeus", Feature: &ARM64.IsZeus},
+		{Name: "isNeoverseV1", Feature: &ARM64.IsNeoverseV1},
 	}
 
 	// arm64 uses different ways to detect CPU features at runtime depending on the operating system.

src/internal/cpu/cpu_arm64_hwcap.go

@@ -52,7 +52,7 @@ func hwcapInit(os string) {
 			ARM64.IsNeoverseN1 = true
 		}
 		if implementor == 'A' && part_num == 0xd40 {
-			ARM64.IsZeus = true
+			ARM64.IsNeoverseV1 = true
 		}
 	}
 }

src/runtime/cpuflags_arm64.go

@@ -11,7 +11,7 @@ import (
 var arm64UseAlignedLoads bool
 
 func init() {
-	if cpu.ARM64.IsNeoverseN1 || cpu.ARM64.IsZeus {
+	if cpu.ARM64.IsNeoverseN1 || cpu.ARM64.IsNeoverseV1 {
 		arm64UseAlignedLoads = true
 	}
 }