x86, mpparse: Move check_slot into CONFIG_X86_IO_APIC context

When CONFIG_X86_MPPARSE=y and CONFIG_X86_IO_APIC=n, then we get
the following warning:

  arch/x86/kernel/mpparse.c:723: warning: 'check_slot' defined but not used

So, put check_slot into CONFIG_X86_IO_APIC context. Its only
called from CONFIG_X86_IO_APIC=y context.
Signed-off-by: Rakib Mullick <rakib.mullick@gmail.com>
LKML-Reference: <AANLkTinsUfGc=NG_GeH_B+zFVu+DXJzZbJKdQLscqfuH@mail.gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

arch/x86/kernel/mpparse.c

@@ -714,10 +714,6 @@ static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
 		*nr_m_spare += 1;
 	}
 }
-#else /* CONFIG_X86_IO_APIC */
-static
-inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
-#endif /* CONFIG_X86_IO_APIC */
 
 static int
 check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
@@ -731,6 +727,10 @@ check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
 
 	return ret;
 }
+#else /* CONFIG_X86_IO_APIC */
+static
+inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
+#endif /* CONFIG_X86_IO_APIC */
 
 static int  __init replace_intsrc_all(struct mpc_table *mpc,
 					unsigned long mpc_new_phys,