TurbineType logic is incorrect after TCF merge

[bjonkman]

Bug description
The logic in the OpenFAST glue code (variable p%TurbineType in subroutine FAST_Init) was not updated with #537, so it still assumes that using HydroDyn + SubDyn means a fixed-bottom offshore turbine. This gets printed in the OpenFAST summary file. @jjonkman recommends removing that logic completely, though turbine type is used in a couple of checks elsewhere in the code, too. Based on other modeling needs (my own!), I suggest that we just differentiate between offshore and onshore turbines for now instead of the further differentiation between fixed and floating offshore.

This is pretty low priority, so I'm documenting the issue here instead of fixing it now.