[tex-k] [web2c] Catch return value from fgets()

[Karl Berry]

    A small nit picked in fixwrites.c; see attached patch.

Thanks, installed (r49132).

In general, ChangeLog entries would be appreciated, since otherwise I
have to write them :).
    
    Aside: Return values from 'dup()' are ignored three times
    in 'texk/kpathsea/tex-make.c'. Does this matter much?

It clearly doesn't matter "much" since no one has ever reported
strangeness, but nevertheless, return values should be checked.
Patch would be welcome ... --thanks, karl.