fixdep: move global variables to local variables of main()

I do not mind global variables where they are useful enough.  In this
case, I do not see a good reason to use global variables since they
are just referenced in shallow places.  It is easy to pass them via
function arguments.

I squashed print_cmdline() into main() since it is just one line code.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>