x86, calgary: fix section mismatch warning - get_tce_space_from_tar

WARNING: vmlinux.o(.text+0x27032): Section mismatch in reference from the function get_tce_space_from_tar() to the function .init.text:calgary_bus_has_devices()
The function get_tce_space_from_tar() references
the function __init calgary_bus_has_devices().
This is often because get_tce_space_from_tar lacks a __init
annotation or the annotation of calgary_bus_has_devices is wrong.

get_tce_space_from_tar is called only from __init function (calgary_init)
and calls __init function (calgary_bus_has_devices).
So annotate it properly.

Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Cc: Chandru Siddalingappa <chandru@in.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>