Log Message:
Fix build.

1. Compile C code with the C compiler, not the fortran compiler.
2. Use f2c, not g95, as the fortran compiler.

XXX  This package builds only with f2c, not g95.
XXX  There does not appear to be any way to specify this other
XXX  than by abusively setting PKGSRC_FORTRAN. So do that for now.