ifpps: Consistently list command line options

Instead of (more or less) arbitrarily listing the command line options,
sort them according to the following rule:

- options with required argument, alphabetically by short option
- options without argument, alphabetically by short option
- common options -v/--version and -h/--help

Do this in the short options string, the long options struct, the
in-program usage and the man page.

Signed-off-by: Tobias Klauser <tklauser@distanz.ch>