Oracle/Sun: Fix Fortran preprocessor rule generation

The SunPro Fortran compiler uses "-F" instead of "-E" to request
preprocessing.  The output does not go to stdout so use "-o" to
specify the output file.

This fixes the guess originally made by commit b6b37e30 (Makefile: Add
assembly and preprocessed targets for Fortran, 2014-11-05).
Merge topic 'sunpro-Fortran-preprocess' into next

be1109d8 Oracle/Sun: Fix Fortran preprocessor rule generation