net: qcom/emac: remove extraneous wake-on-lan code

The EMAC driver does not support wake-on-lan, but there is still
code left-over that partially enables it.  Remove that code and a few
macros that support it.

Signed-off-by: Timur Tabi <timur@codeaurora.org>
Signed-off-by: David S. Miller <davem@davemloft.net>