[ORC] MapperJITLinkMemoryManager should deinitialize on abandon, not deallocate.

The JITLinkMemoryManager::InFlightAlloc::abandon method should only abandon
memory for the current allocation, not any other allocations. In
MapperJITLinkMemoryManager this corresponds to the deinitialize operation, not
the deallocate operation (which releases whole slabs of memory that may be
shared by many allocations).

No testcase: This was spotted by inspection. The failing program was linking
concurrently when one linker instance raised an error. Through the call to
abandon an entire underlying slab was deallocated, resulting in segfaults in
other concurrent links that were sharing that slab.

Author: Lang Hames

llvm/lib/ExecutionEngine/Orc/MapperJITLinkMemoryManager.cpp

@@ -43,7 +43,7 @@ class MapperJITLinkMemoryManager::InFlightAlloc
   }
 
   void abandon(OnAbandonedFunction OnFinalize) override {
-    Parent.Mapper->release({AllocAddr}, std::move(OnFinalize));
+    Parent.Mapper->deinitialize({AllocAddr}, std::move(OnFinalize));
   }
 
 private: