x86: Move pre_intr_init to x86_init_ops

Replace the quirk machinery by a x86_init_ops function which
defaults to the standard implementation. This is also a preparatory
patch for Moorestown support which needs to replace the default
init_ISA_irqs as well.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

arch/x86/include/asm/irq.h

@@ -47,4 +47,6 @@ extern unsigned int do_IRQ(struct pt_regs *regs);
 extern DECLARE_BITMAP(used_vectors, NR_VECTORS);
 extern int vector_used_by_percpu_irq(unsigned int vector);
 
+extern void init_ISA_irqs(void);
+
 #endif /* _ASM_X86_IRQ_H */