mfd: tps6105x: Use managed resources when allocating memory

This patch introduces the use of devm_kzalloc instead of the
corresponding unmanaged version and does away with the kfrees in the
probe and remove functions. Also, a label is done away with.

Signed-off-by: Himangi Saraogi <himangi774@gmail.com>
Acked-by: Julia Lawall <julia.lawall@lip6.fr>
Signed-off-by: Lee Jones <lee.jones@linaro.org>