cxgb4: update 1.20.8.0 as the latest firmware supported

Change t4fw_version.h to update latest firmware version
number to 1.20.8.0.

Signed-off-by: Ganesh Goudar <ganeshgr@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
1 file changed