[fortran patch] Don't use TREE_LISTs for storing arguments to intrinsic functions

[Brooks Moses]

Lee Millward wrote:
> Here's an updated patch that addresses the last round of comments from
> Brooks. Apologies for the delay in getting this posted, I had to stop
> working on this to focus on my finals just before I could get
> everything sorted :-(.
> 
> This version has been bootstrapped and regression tested with no new
> failures on i686-pc-linux-gnu, ok to apply?

This is OK with the change FX requested, assuming that it passes the 
regression testing.  Please go ahead and apply it once it's tested.  :)

Thanks,
- Brooks