e1000: drop dead pcie code from e1000

this patch is the first in a series of clean up patches for e1000 to drop
unused code, and update the driver to kernel spec, and then, to update the
driver to have all available bug fixes.

Call it the e1000 weight loss plan.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Don Skidmore <donald.c.skidmore@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>