[compiler-rt] Remove dlsym interceptor for HSA UBSan (#227022)
Summary:
This existed to handle the OpenMP case that dynamically opened via
`dlsym`. However, https://github.com/llvm/llvm-project/pull/227020
removes the need for this by first checking the global space first.
The main motivation is that the `dlsym` interceptor layer was the most
janky part of this whole affair and was a major blocker to supporting
`-shared-libsan` in https://github.com/llvm/llvm-project/pull/226551.