Suppress "user not found" log when post not found

This also saves a user suspension check when a post isn't found.

posts.go

@@ -381,10 +381,13 @@ func handleViewPost(app *App, w http.ResponseWriter, r *http.Request) error {
 		}
 	}
 
-	suspended, err := app.db.IsUserSuspended(ownerID.Int64)
+	var suspended bool
+	if found {
+		suspended, err = app.db.IsUserSuspended(ownerID.Int64)
 		if err != nil {
 			log.Error("view post: %v", err)
 		}
+	}
 
 	// Check if post has been unpublished
 	if content == "" {