sh_eth: Remove obsolete explicit clock handling for WoL

sh_eth: Remove obsolete explicit clock handling for WoL

Currently, if Wake-on-LAN is enabled, the SH-ETH device's module clock
is manually kept running during system suspend, to make sure the device
stays active.

Since commits 91c719f5ec6671f7 ("soc: renesas: rcar-sysc: Keep wakeup
sources active during system suspend") and 744dddcae84441b1 ("clk:
renesas: mstp: Keep wakeup sources active during system suspend"), this
workaround is no longer needed.  Hence remove all explicit clock
handling to keep the device active.

Signed-off-by: Geert Uytterhoeven <[email protected]>
Reviewed-by: Niklas Söderlund <[email protected]>
Reviewed-by: Sergei Shtylyov <[email protected]>
Signed-off-by: David S. Miller <[email protected]>