[lldb] Also disable de-registration of EHFrames in IRExecutionUnit

Summary:
We disabled registration by providing an empty `registerEHFrames`, so we should also provide an empty `deregisterEHFrames`
in case that function relies on `registerEHFrames` being called before. Currently `deregisterEHFrames` is a no-op anyway
as it just iterates over the (empty( list of registered EHFrames and then clear the empty list.

Reviewers: davide, JDevlieghere

Reviewed By: JDevlieghere

Subscribers: JDevlieghere, lldb-commits

Tags: #upstreaming_lldb_s_downstream_patches, #lldb

Differential Revision: https://reviews.llvm.org/D69713

lldb/include/lldb/Expression/IRExecutionUnit.h

@@ -298,8 +298,10 @@ private:
       return false;
     }
 
+    // Ignore any EHFrame registration.
     void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr,
                           size_t Size) override {}
+    void deregisterEHFrames() override {}
 
     uint64_t getSymbolAddress(const std::string &Name) override;