[IA64] fix phys. address conversion in ia64_pal_tr_read

The palinfo module may call ia64_pal_tr_read using an IPI.  If the processor
receiving the IPI is idle, the call will fail since the idle process stack is
in region 5 and ia64_pal_tr_read uses __pa rather than ia64_tpa.  This small
patch fixes the problem by making it use ia64_tpa instead.
Signed-off-by: Jesse Barnes <jbarnes@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

include/asm-ia64/pal.h

@@ -1531,7 +1531,7 @@ static inline s64
 ia64_pal_tr_read (u64 reg_num, u64 tr_type, u64 *tr_buffer, pal_tr_valid_u_t *tr_valid)
 {
 	struct ia64_pal_retval iprv;
-	PAL_CALL_PHYS_STK(iprv, PAL_VM_TR_READ, reg_num, tr_type,(u64)__pa(tr_buffer));
+	PAL_CALL_PHYS_STK(iprv, PAL_VM_TR_READ, reg_num, tr_type,(u64)ia64_tpa(tr_buffer));
 	if (tr_valid)
 		tr_valid->piv_val = iprv.v0;
 	return iprv.status;