This change introduces Comet Lake Mobile Platform support in the e1000
driver along with shared code patches described below.

- Cast return value of e1000_ltr2ns() to higher type to avoid overflow
- Remove useless statement of assigning act_offset
- Add initialization of identification LED
- Fix flow control setup after connected standby:
  After connected standby the driver blocks resets during
  "AdapterStart" and skips flow control setup. This change adds
  condition in e1000_setup_link_ich8lan() to always setup flow control
  and to setup physical interface only when there is no need to block
  resets.

Signed-off-by: Piotr Pietruszewski <piotr.pietruszewski@intel.com>

Submitted by:	Piotr Pietruszewski <piotr.pietruszewski@intel.com>
Reviewed by:	erj@
Tested by:	Jeffrey Pieper <jeffrey.e.pieper@intel.com>
MFC after:	1 week
Relnotes:	yes
Sponsored by:	Intel Corporation
Differential Revision:	https://reviews.freebsd.org/D25035