[FORCEDETH]: Fix reversing the MAC address on suspend.

For cards that initially have the MAC address stored in reverse order,
the forcedeth driver uses a flag to signal whether the address was
already corrected, so that it is not reversed again on a subsequent
probe.

Unfortunately this flag, which is stored in a register of the card,
seems to get lost during suspend, resulting in the MAC address being
reversed again. To fix that, the MAC address needs to be written back
in reversed order before we suspend and the flag needs to be reset.

The flag is still required because at least kexec will never write
back the reversed address and thus needs to know what state the card
is in.

Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: David S. Miller <davem@davemloft.net>