powerpc/cell: Use handle_edge_eoi_irq for real

Missed one instance when moving that to the core code.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Cc: michael@ellerman.id.au
Cc: mingo@elte.hu
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>