o multiple modules can be unloaded at once (specified either by id or be
module name)
o exit with EX_USAGE after usage() is called.
o remove unused variables, since we keep command line flags as bitmask,
in 'opt'.
o 'kldload -n ...' does nothing. Add comment to this options.
Additionally:
o Update manual page to conform new functionality.
o Increace WARNS to 6. Because we can.
Approved by: cognet (mentor)
MFC after: 1 week
fix a few problems with missing headers, warn called with an exit
value, and undeclared getopt vars
these programs now compile -Wall clean (and yes, I know I should use
more than just -Wall) :)