net: amd-xgbe: Check only the minimum speed for active/passive cables

There are cables that exist that can support speeds in excess of 10GbE.
The driver, however, restricts the EEPROM advertised nominal bitrate to
a specific range, which can prevent usage of cables that can support,
for example, up to 25GbE.

Rather than checking that an active or passive cable supports a specific
range, only check for a minimum supported speed.

Fixes: abf0a1c2 ("amd-xgbe: Add support for SFP+ modules")
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: David S. Miller <davem@davemloft.net>