net: fec: replace delayed work with standard work

As of "better implementation of iMX6 ERR006358 quirk", we no longer have
a requirement for a delayed work.  Moreover, the work is now only used
for timeout purposes, so the timeout flag is also pointless - we set it
each time we queue the work, and the work clears it.

Replace the fec_enet_delayed_work struct with a standard work_struct,
resulting in simplified timeout handling code.

Acked-by: Fugang Duan <B38611@freescale.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>