x86: mpparse.c: fix section mismatch warning

WARNING: vmlinux.o(.text+0x118f7): Section mismatch in reference from the function construct_ioapic_table() to the function .init.text:MP_bus_info()
The function construct_ioapic_table() references
the function __init MP_bus_info().
This is often because construct_ioapic_table lacks a __init
annotation or the annotation of MP_bus_info is wrong.

construct_ioapic_table is called only from construct_default_ISA_mptable which is __init

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/kernel/mpparse.c

@@ -484,7 +484,7 @@ static void __init construct_default_ioirq_mptable(int mpc_default_type)
 }
 
 
-static void construct_ioapic_table(int mpc_default_type)
+static void __init construct_ioapic_table(int mpc_default_type)
 {
 	struct mpc_config_ioapic ioapic;
 	struct mpc_config_bus bus;
@@ -529,7 +529,7 @@ static void construct_ioapic_table(int mpc_default_type)
 	construct_default_ioirq_mptable(mpc_default_type);
 }
 #else
-static inline void construct_ioapic_table(int mpc_default_type) { }
+static inline void __init construct_ioapic_table(int mpc_default_type) { }
 #endif
 
 static inline void __init construct_default_ISA_mptable(int mpc_default_type)