pwm: atmel-tcb: Harmonize resource allocation order

Allocate driver data as first resource in the probe function. This way it
can be used during allocation of the other resources (instead of assigning
these to local variables first and update driver data only when it's
allocated). Also as driver data is allocated using a devm function this
should happen first to have the order of freeing resources in the error
path and the remove function in reverse.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>