Core: Merge Direct Memory Areas (#3084)

* Merge dmem areas

* Fix DirectMemoryArea::CanMergeWith

Don't merge dmem areas if the memory types are different.

* Reduce some warnings to info

Both functions should behave properly now, there's no reason to warn about their use.

* Clang

src/core/memory.h

@@ -75,6 +75,9 @@ struct DirectMemoryArea {
         if (base + size != next.base) {
             return false;
         }
+        if (memory_type != next.memory_type) {
+            return false;
+        }
         if (is_free != next.is_free) {
             return false;
         }