Revert "eth: remove the DLink/Sundance (ST201) driver"

This reverts commit 8401a108.

I got a report from an (anonymous) Sundance user:

  Ethernet controller: Sundance Technology Inc / IC Plus Corp IC Plus IP100A Integrated 10/100 Ethernet MAC + PHY (rev 31)

Revert the driver back in. Make following changes:
 - update Denis's email address in MAINTAINERS
 - adjust to timer API renames:
   - del_timer_sync() -> timer_delete_sync()
   - from_timer() -> timer_container_of()

Fixes: 8401a108 ("eth: remove the DLink/Sundance (ST201) driver")
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250901210818.1025316-1-kuba@kernel.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>