Small fixes.

Changes:
  - _inet.c:64_ `l` is unsigned so checking for `<= 0` is pointless.
  - _unix/getaddrinfo.c:152_ `buf` is never free'd.
  - _win/fs.c:1051_ `buf` is never free'd.
  - _win/tty.c:99_ `handle` is assigned a value in line 103.
  - _win/tty.c:989_ `FOREGROUND_RED` is bitwise-OR'd with `FOREGROUND_RED`.

I'm not really that familiar with the code-base so excuse any stupidity but
these are a few small things I noticed.