sparseirq: fix typo in !CONFIG_IO_APIC case

Impact: build fix
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/include/asm/io_apic.h

@@ -195,10 +195,7 @@ extern void probe_nr_irqs_gsi(void);
 static const int timer_through_8259 = 0;
 static inline void ioapic_init_mappings(void)	{ }
 
-static inline int probe_nr_irqs(void)
-{
-	return NR_IRQS;
-}
+static inline void probe_nr_irqs_gsi(void)	{ }
 #endif
 
 #endif /* _ASM_X86_IO_APIC_H */