docs/man/mangen.go: fix type error

When calling flag.Bool(), we note that it returns a bool pointer
(`*bool`), instead of bool value (`bool`). As such, let's make sure that
we de-reference *bool -> bool before performing operations against it.

docs/man/mangen.go

@@ -13,7 +13,7 @@ import (
 )
 
 func infof(w io.Writer, format string, a ...interface{}) {
-	if !verbose {
+	if !*verbose {
 		return
 	}
 	fmt.Fprintf(w, format, a...)