cxgbe(4): Update firmwares to 1.27.4.0

This is the list of changes since last release, taken from the release
notes of Chelsio Unified Wire 3.18.0.1.

Version : 1.27.4.0

Date : 07/05/2023

Fixes

BASE:

• Handle 40G to 100G cable change.
• Avoid unnecessary i2c read.

Obtained from: Chelsio Communications
Sponsored by: Chelsio Communications
MFC after: 1 week