nfo() references
a variable __initdata x86_quirks.
If x86_quirks is only used by MP_processor_info then
annotate x86_quirks with a matching annotation.

MP_processor_info uses x86_quirks which is __init and is used only from
smp_read_mpc and construct_default_ISA_mptable which are __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>