linux-phytec-ti

gpio: xlp: use resource management for irqs

Use the resource managed variant of irq_alloc_descs() and remove the
code manually freeing allocated interrupt descriptors.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>