s4-heimdal: Remove the execute flag of cfx.c.
s4-heimdal: Remove the execute flag of cfx.c.

The scripts which are extracting debuginfo are looking for files with
the executable bit and find cfx.c which isn't a executable.

madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal,madscientist159/heimdal