mfd: palmas: Drop kfree of devm_kzalloc's data

Using kfree to free data allocated with devm_kzalloc causes double frees.

The semantic patch that fixes this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression x;
@@

x = devm_kzalloc(...)
...
?-kfree(x);
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>