[IA64] Fix wrong insertion of TLB entry in region 0

[IA64] Fix wrong insertion of TLB entry in region 0

On PV domain with metaphysical mode, emulation of itc.d in region 0
doesn't work well and inserts an wrong TC entry.
Because set_one_rr() doesn't set the machine region register.
i.e. metaphyisical_rr0 is used instead of guest's rr[0].

This bug causes Dom0/U crash when an application uses region 0.
Actually I met the crash when I was building open GFW (java uses
region 0).

Signed-off-by: Kouya Shimura <kouya@jp.fujitsu.com>