amd-xgbe: Guard against incorrectly generated interrupts

Due to a hardware issue, it is possible for interrupt events to be
incorrectly generated when performing a soft reset.  To guard against
this, perform the soft reset twice.

Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>