drivers: net: davinci_cpdma: remove kfree on objects allocated with devm_* apis

memories allocated with devm_* apis must not be freed with kfree apis,
so removing the kfree calls

Fixes: e1943128

 ('drivers: net: davinci_cpdma: Convert kzalloc() to devm_kzalloc().')

Signed-off-by: Mugunthan V N <mugunthanvnm@ti.com>
Signed-off-by: David S. Miller <davem@davemloft.net>