Fix errors caught by go vet in compliance package

`go test` implicitly runs `go vet` and fails the tests if vet
errors are found.  Fix all the issues found by vet.

Test: go test build/make/tools/compliance/...
Change-Id: If0684cf124ece4931af440008cd44a61c22de475
diff --git a/tools/compliance/cmd/htmlnotice.go b/tools/compliance/cmd/htmlnotice.go
index cff1ff8..3456a49 100644
--- a/tools/compliance/cmd/htmlnotice.go
+++ b/tools/compliance/cmd/htmlnotice.go
@@ -74,12 +74,12 @@
 	} else {
 		dir, err := filepath.Abs(filepath.Dir(*outputFile))
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "cannot determine path to %q: %w\n", *outputFile, err)
+			fmt.Fprintf(os.Stderr, "cannot determine path to %q: %s\n", *outputFile, err)
 			os.Exit(1)
 		}
 		fi, err := os.Stat(dir)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "cannot read directory %q of %q: %w\n", dir, *outputFile, err)
+			fmt.Fprintf(os.Stderr, "cannot read directory %q of %q: %s\n", dir, *outputFile, err)
 			os.Exit(1)
 		}
 		if !fi.IsDir() {
@@ -107,7 +107,7 @@
 	if *outputFile != "-" {
 		err := os.WriteFile(*outputFile, ofile.(*bytes.Buffer).Bytes(), 0666)
 		if err != nil {
-			fmt.Fprintf(os.Stderr, "could not write output to %q: %w\n", *outputFile, err)
+			fmt.Fprintf(os.Stderr, "could not write output to %q: %s\n", *outputFile, err)
 			os.Exit(1)
 		}
 	}
@@ -139,13 +139,13 @@
 	}
 
 	fmt.Fprintln(ctx.stdout, "<!DOCTYPE html>")
-	fmt.Fprintln(ctx.stdout, "<html><head>\n")
+	fmt.Fprintln(ctx.stdout, "<html><head>")
 	fmt.Fprintln(ctx.stdout, "<style type=\"text/css\">")
 	fmt.Fprintln(ctx.stdout, "body { padding: 2px; margin: 0; }")
 	fmt.Fprintln(ctx.stdout, "ul { list-style-type: none; margin: 0; padding: 0; }")
 	fmt.Fprintln(ctx.stdout, "li { padding-left: 1em; }")
 	fmt.Fprintln(ctx.stdout, ".file-list { margin-left: 1em; }")
-	fmt.Fprintln(ctx.stdout, "</style>\n")
+	fmt.Fprintln(ctx.stdout, "</style>")
 	if 0 < len(ctx.title) {
 		fmt.Fprintf(ctx.stdout, "<title>%s</title>\n", html.EscapeString(ctx.title))
 	}