cxgb4: clean up init_one

clean up init_one and use chip_ver consistently throughout
init_one() for chip version.

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