printer: add generated code warnings

examples/add/add.s

@@ -1,3 +1,4 @@
+// Code generated by command: go run asm.go -out add.s -stubs stub.go. DO NOT EDIT.
 
 #include "textflag.h"
 

examples/add/stub.go

@@ -1,3 +1,5 @@
+// Code generated by command: go run asm.go -out add.s -stubs stub.go. DO NOT EDIT.
+
 package add
 
 func Add(x uint64, y uint64) uint64

examples/complex/complex.s

@@ -1,3 +1,4 @@
+// Code generated by command: go run asm.go -out complex.s -stubs stub.go. DO NOT EDIT.
 
 #include "textflag.h"
 

examples/complex/stub.go

@@ -1,5 +1,9 @@
+// Code generated by command: go run asm.go -out complex.s -stubs stub.go. DO NOT EDIT.
+
 package complex
 
 func Real(x complex128) float64
+
 func Imag(x complex128) float64
+
 func Norm(x complex128) float64

examples/components/components.s

@@ -1,3 +1,4 @@
+// Code generated by command: go run asm.go -out components.s -stubs stub.go. DO NOT EDIT.
 
 #include "textflag.h"
 

examples/components/stub.go

@@ -1,15 +1,29 @@
+// Code generated by command: go run asm.go -out components.s -stubs stub.go. DO NOT EDIT.
+
 package components
 
 func FieldByte(s Struct) byte
+
 func FieldInt8(s Struct) int8
+
 func FieldUint16(s Struct) uint16
+
 func FieldInt32(s Struct) int32
+
 func FieldUint64(s Struct) uint64
+
 func FieldFloat32(s Struct) float32
+
 func FieldFloat64(s Struct) float64
+
 func FieldStringLen(s Struct) int
+
 func FieldSliceCap(s Struct) int
+
 func FieldArrayTwoBTwo(s Struct) byte
+
 func FieldArrayOneC(s Struct) uint16
+
 func FieldComplex64Imag(s Struct) float32
+
 func FieldComplex128Real(s Struct) float64

examples/fnv1a/fnv1a.s

@@ -1,3 +1,4 @@
+// Code generated by command: go run asm.go -out fnv1a.s -stubs stub.go. DO NOT EDIT.
 
 #include "textflag.h"
 

examples/fnv1a/stub.go

@@ -1,3 +1,5 @@
+// Code generated by command: go run asm.go -out fnv1a.s -stubs stub.go. DO NOT EDIT.
+
 package fnv1a
 
 func Hash64(data []byte) uint64

examples/sum/stub.go

@@ -1,3 +1,5 @@
+// Code generated by command: go run asm.go -out sum.s -stubs stub.go. DO NOT EDIT.
+
 package sum
 
 func Sum(xs []uint64) uint64

examples/sum/sum.s

@@ -1,3 +1,4 @@
+// Code generated by command: go run asm.go -out sum.s -stubs stub.go. DO NOT EDIT.
 
 #include "textflag.h"