Make sure a pad is at least as big as its hole in the RTree.

Fixes https://gitlab.com/kicad/code/kicad/issues/9516

pcbnew/drc/drc_rtree.h

@@ -27,6 +27,7 @@
 
 #include <eda_rect.h>
 #include <board_item.h>
+#include <pad.h>
 #include <fp_text.h>
 #include <memory>
 #include <unordered_set>
@@ -35,6 +36,7 @@
 
 #include <geometry/rtree.h>
 #include <geometry/shape.h>
+#include <geometry/shape_segment.h>
 #include <math/vector2d.h>
 
 /**
@@ -99,6 +101,17 @@ public:
         else
             subshapes.push_back( shape.get() );
 
+        if( aItem->Type() == PCB_PAD_T )
+        {
+            PAD* pad = static_cast<PAD*>( aItem );
+
+            if( pad->GetDrillSizeX() )
+            {
+                const SHAPE* hole = pad->GetEffectiveHoleShape();
+                subshapes.push_back( const_cast<SHAPE*>( hole ) );
+            }
+        }
+
         for( SHAPE* subshape : subshapes )
         {
             BOX2I bbox = subshape->BBox();