Some chips may not allow changing default speed when dual rate
transceivers modules are used. Firmware on those chips will
indicate the same to the driver.

Add a warning message when speed change is not supported
because a dual rate transceiver is detected by the NIC.
Signed-off-by: Sreekanth Reddy <sreekanth.reddy@broadcom.com>
Reviewed-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: Pavan Chebbi <pavan.chebbi@broadcom.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://lore.kernel.org/r/20240402093753.331120-8-pavan.chebbi@broadcom.comSigned-off-by: Jakub Kicinski <kuba@kernel.org>