Having only known this name from Lord of the Rings (and knowing how most of Tolkien's names are made-up and not used as real names), I was surprised to find out that Drogo is a real name. I like it. It sounds like a warrior (despite the fact that Drogo wasn't a warrior in Lord of the Rings). This is one of those few names from Lord of the Rings that I could try to get away with using.
I can't see a person actually having this name.