drivers/net/Kconfig: Hide REALTEK_8168_RESET in menuconfig

Resetting a Realtek 8168 NIC only makes sense on targets that have
such a device.

Change-Id: I8ac9e8da1d8ecaacb19b4610a9b75f107915d691
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/17577
Tested-by: build bot (Jenkins)
Reviewed-by: Nico Huber <nico.h@gmx.de>
1 file changed