drivers/net: fix up stale paths from driver reorg

The reorganization of the driver layout in drivers/net
left behind some stale paths in comments and in Kconfig
help text.  Bring them up to date.  No actual change to
any code takes place here.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
CC: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>