cmd/compile/internal/ssa: cleanup godocs

Add a blank line before the "package ssa" lines so the "autogenerated
don't edit" comments don't end up in godoc output.

Change-Id: I82bf90d52d426ce1a8e21483fc8f47b3689259c7
Reviewed-on: https://go-review.googlesource.com/20086
Reviewed-by: Keith Randall <khr@golang.org>
diff --git a/src/cmd/compile/internal/ssa/gen/main.go b/src/cmd/compile/internal/ssa/gen/main.go
index 5ba8483f..660511e 100644
--- a/src/cmd/compile/internal/ssa/gen/main.go
+++ b/src/cmd/compile/internal/ssa/gen/main.go
@@ -75,6 +75,7 @@
 	w := new(bytes.Buffer)
 	fmt.Fprintf(w, "// autogenerated: do not edit!\n")
 	fmt.Fprintf(w, "// generated from gen/*Ops.go\n")
+	fmt.Fprintln(w)
 	fmt.Fprintln(w, "package ssa")
 
 	fmt.Fprintln(w, "import \"cmd/internal/obj/x86\"")
diff --git a/src/cmd/compile/internal/ssa/gen/rulegen.go b/src/cmd/compile/internal/ssa/gen/rulegen.go
index c2da3e6..e3e3efa 100644
--- a/src/cmd/compile/internal/ssa/gen/rulegen.go
+++ b/src/cmd/compile/internal/ssa/gen/rulegen.go
@@ -140,6 +140,7 @@
 	w := new(bytes.Buffer)
 	fmt.Fprintf(w, "// autogenerated from gen/%s.rules: do not edit!\n", arch.name)
 	fmt.Fprintln(w, "// generated with: cd gen; go run *.go")
+	fmt.Fprintln(w)
 	fmt.Fprintln(w, "package ssa")
 	if *genLog {
 		fmt.Fprintln(w, "import \"fmt\"")
diff --git a/src/cmd/compile/internal/ssa/opGen.go b/src/cmd/compile/internal/ssa/opGen.go
index e912b20..a48766ff 100644
--- a/src/cmd/compile/internal/ssa/opGen.go
+++ b/src/cmd/compile/internal/ssa/opGen.go
@@ -1,5 +1,6 @@
 // autogenerated: do not edit!
 // generated from gen/*Ops.go
+
 package ssa
 
 import "cmd/internal/obj/x86"
diff --git a/src/cmd/compile/internal/ssa/rewriteAMD64.go b/src/cmd/compile/internal/ssa/rewriteAMD64.go
index 61a6178..83fc437 100644
--- a/src/cmd/compile/internal/ssa/rewriteAMD64.go
+++ b/src/cmd/compile/internal/ssa/rewriteAMD64.go
@@ -1,5 +1,6 @@
 // autogenerated from gen/AMD64.rules: do not edit!
 // generated with: cd gen; go run *.go
+
 package ssa
 
 import "math"
diff --git a/src/cmd/compile/internal/ssa/rewritegeneric.go b/src/cmd/compile/internal/ssa/rewritegeneric.go
index 0c71b2c..ad2abc5 100644
--- a/src/cmd/compile/internal/ssa/rewritegeneric.go
+++ b/src/cmd/compile/internal/ssa/rewritegeneric.go
@@ -1,5 +1,6 @@
 // autogenerated from gen/generic.rules: do not edit!
 // generated with: cd gen; go run *.go
+
 package ssa
 
 import "math"