sh: remove sh7780 interrupt controller hack from pci code

This patch removes the sh778x specific pci code that pokes in the
interrupt controller and overwrites things. The new and improved IRL
code manages this in plat_irq_setup() and plat_irq_setup_pins()
instead.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>