cxgb4: add new T5 pci device id's

Add 0x50a5, 0x50a6, 0x50a7, 0x50a8 and 0x50a9 T5 device
id's.

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