Fixed a crasher where when a ProcessGDBRemote class was being destroyed, it...

Fixed a crasher where when a ProcessGDBRemote class was being destroyed, it would eventually destroy the dynamic loader (when the lldb_private::Process::m_dynamic_loader_ap destroys itself in the object member destructor chain). The dynamic loader was calling a pure virtual method in Process which was causing a crash. The quick fix is to reset the auto pointer in the ProcessGDBRemote destructor when  ProcessGDBRemote is still a valid object with all its pure virtual functions intact.

llvm-svn: 121704