fbcon: replace snprintf in show functions with sysfs_emit

Use sysfs_emit instead of scnprintf or sprintf.
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Yang Guang <yang.guang5@zte.com.cn>
Signed-off-by: Helge Deller <deller@gmx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/0cb7ca73d9cd7162988a22a24cd18bbcd3d8bb27.1638156341.git.yang.guang5@zte.com.cn

drivers/video/fbdev/core/fbcon.c

@@ -3185,7 +3185,7 @@ static ssize_t show_rotate(struct device *device,
 	rotate = fbcon_get_rotate(info);
 err:
 	console_unlock();
-	return snprintf(buf, PAGE_SIZE, "%d\n", rotate);
+	return sysfs_emit(buf, "%d\n", rotate);
 }
 
 static ssize_t show_cursor_blink(struct device *device,
@@ -3210,7 +3210,7 @@ static ssize_t show_cursor_blink(struct device *device,
 	blink = delayed_work_pending(&ops->cursor_work);
 err:
 	console_unlock();
-	return snprintf(buf, PAGE_SIZE, "%d\n", blink);
+	return sysfs_emit(buf, "%d\n", blink);
 }
 
 static ssize_t store_cursor_blink(struct device *device,