m68k/irq: Remove obsolete support for user vector interrupt fixups

It was used on Apollo only, before its conversion to genirq.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
diff --git a/arch/m68k/apollo/dn_ints.c b/arch/m68k/apollo/dn_ints.c
index b7d0aa3..17be1e7 100644
--- a/arch/m68k/apollo/dn_ints.c
+++ b/arch/m68k/apollo/dn_ints.c
@@ -41,7 +41,7 @@
 
 void __init dn_init_IRQ(void)
 {
-	m68k_setup_user_interrupt(VEC_USER + 96, 16, NULL);
+	m68k_setup_user_interrupt(VEC_USER + 96, 16);
 	m68k_setup_irq_controller(&apollo_irq_chip, handle_fasteoi_irq,
 				  IRQ_APOLLO, 16);
 }