We went about 4 years ago and they did have hiardryers as I rmember they were not the ones that many have in the bathroom that are plastic and go hot and really do not work on my hair as it is so thick and my arm begins to ache. If I recall they were in the drawer in the vanity area. Hope you have a lovely cruise.
All state rooms on Royal Caribbean International ships have a hair dryer in one of the drawers in the vanity area. I have just joined the company and was pleased to find on my first ship- Liberty of the Seas- that they are as the previous writer says- not the rubbish kind that make your hair frizz but actually pretty decent and there's plenty of room to get ready without getting hot and bothered!! Please remember if you take your own (or straighteners) that you will need a plug adaptor! I recommend taking a USA one and a European one as their are both in your state room.
Have a wonderful time on Voyager of the Seas! Anna.