[patch, fortran] Improve dependency checking

[Thomas Koenig]

Hi Steve,

> Ah, I don't speak C++, and didn't know one could corrupt a
> C prototype in this manner.  A quick glance of gfortran.h
> indeed shows a few more occurences of "bool xxx = false".
> I suppose the patch is then OK.

I don't use many C++ features, but I use this one because I feel
it should really be in C :-)

> PS: watch for long lines.

Corrected and committed as r273807.

Thanks for the review!

Regards

	Thomas