fix switchover WRT interrupts

cpu/base_cpu.cc:
    gah! copy the interrupt status on switchover

--HG--
extra : convert_revision : d3199a7409a494b7687354c43ffca697f37e8456

cpu/base_cpu.cc

@@ -184,6 +184,10 @@ BaseCPU::takeOverFrom(BaseCPU *oldCPU)
         newXC->process->replaceExecContext(newXC->cpu_id, newXC);
 #endif
     }
+
+    for (int i = 0; i < NumInterruptLevels; ++i)
+        interrupts[i] = oldCPU->interrupts[i];
+    intstatus = oldCPU->intstatus;
 }