gpio: thunderx: Use the default parent apis for {request,release}_resources

thunderx_gpio_irq_{request,release}_resources apis are trying to
{request,release} resources on parent interrupt. There are default
apis doing the same. Use the default parent apis instead of writing
the same code snippet.

Cc: linux-gpio@vger.kernel.org
Cc: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lokesh Vutla <lokeshvutla@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>