No. You are more than welcome to encourage your FB friends to check out your work on HP. The only danger is "over promoting" your work on FB. Nobody likes to have their walls or home pages filled with spamming content from people on their friends list. You could risk losing some of your FB friends if you do that.
However, if you have published a hub that you think people on your FB list will genuinely enjoy or find interesting, HP encourages you to share it. The key to using FB to promote your work is moderation.
HP has an great entry in the Learning Centre about how best to use FB to promote your work here in HP. You can find it here:
Good luck & Happy Hubbing!