net: txgbe: Update module description

Because of the addition of support for 25G/40G devices, update the module
description.

Signed-off-by: Jiawen Wu <jiawenwu@trustnetic.com>
Link: https://patch.msgid.link/20250414022421.375101-1-jiawenwu@trustnetic.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>