chelsio: Fix a typo in a function name

It is likely that 'my3216_poll()' should be 'my3126_poll()'. (1 and 2
switched in 3126.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>