gpio/mpc8xxx: Consolidate chained IRQ handler install/remove

gpio/mpc8xxx: Consolidate chained IRQ handler install/remove

Chained irq handlers usually set up handler data as well. We now have
a function to set both under irq_desc->lock. Replace the two calls
with one.

Search and conversion was done with coccinelle:

Reported-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Alexandre Courbot <gnurou@gmail.com>
Cc: linux-gpio@vger.kernel.org