e1000e: cosmetic move of #defines and prototypes to the new manage.h

Move #defines, function prototypes and data types which are applicable to
all/most devices supported by the driver but are specific to the
manageability component of each device to the new manage.h header file.
These #defines, function prototypes and data types can be used by other
files in the driver and moving them to the manageability-specific file
makes it clearer to which component they are applicable.

Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>