python: Simplify connectPorts() around EtherObject/EtherDevice.
python: Simplify connectPorts() around EtherObject/EtherDevice.

EtherDevice now inherits EtherObject and shares the same getEthPort
virtual function, so there's no need to treat them separately any more.

Change-Id: Ia6c147fd97fece4a281c296521a7b095f793d32e
Reviewed-on: https://gem5-review.googlesource.com/c/public/gem5/+/17030
Reviewed-by: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>
Maintainer: Andreas Sandberg <c9f5686ee5bd561c93f9de79681eee75bfa7f36e@arm.com>

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