Update to low level hardware code.  Adds support for the new 
82540 device.  Replaces e1000_mac.c e1000_mac.h e1000_phy.c and 
e1000_phy.h with e1000_hw.c and e1000_hw.c.  Changes to the 
makefile, header includes, and some minor function syntax 
changes to get the driver working with the new code.