Abort if register_dma_int.

Make register_dma_int cause Abort for heathrow and ohare like it does for amic.

devices/ioctrl/heathrow.cpp

@@ -384,6 +384,7 @@ uint32_t HeathrowIC::register_dev_int(IntSrc src_id)
 
 uint32_t HeathrowIC::register_dma_int(IntSrc src_id)
 {
+    ABORT_F("Heathrow: register_dma_int() not implemented");
     return 0;
 }
 

devices/ioctrl/ohare.cpp

@@ -213,6 +213,7 @@ uint32_t OHare::register_dev_int(IntSrc src_id)
 
 uint32_t OHare::register_dma_int(IntSrc src_id)
 {
+    ABORT_F("OHare: register_dma_int() not implemented");
     return 0;
 }