cmd/internal: fix bug getting wrong indicator in DRconv()

Change-Id: I251ae497b0ab237d4b3fe98e397052394142d437
Reviewed-on: https://go-review.googlesource.com/41653Reviewed-by: Cherry Zhang <cherryyz@google.com>
Run-TryBot: Cherry Zhang <cherryyz@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>

src/cmd/internal/obj/arm64/anames7.go

@@ -4,6 +4,7 @@
 
 package arm64
 
+// This order should be strictly consistent to that in a.out.go
 var cnames7 = []string{
 	"NONE",
 	"REG",
@@ -16,13 +17,13 @@ var cnames7 = []string{
 	"SPR",
 	"COND",
 	"ZCON",
+	"ABCON0",
 	"ADDCON0",
+	"ABCON",
 	"ADDCON",
+	"MBCON",
 	"MOVCON",
 	"BITCON",
-	"ABCON0",
-	"ABCON",
-	"MBCON",
 	"LCON",
 	"VCON",
 	"FCON",