You can either way in this case.
I always brine regardless of whether the bird came that way.
Why?For me brining is way to bring in extra flavors that a plain turkey just doesn't have.I like a fruit juice(cranberry) based brine with garlic and fresh herbs,gives the meat a nice light flavor.So many different things can be added to the brine base.
I've never had an issue with a pre-brined bird being to salty after a second brining.
Also take a look at this recent thread:
I purchased two Honeysuckle White boneless turkey breasts. The label shows that they're already in an 18% solution. Would I necessarily gain anything by doing an additional brine before I smoke them, or am I just setting myself up for a salty mess?
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