This commit shrinks the `RelocationTarget` enumeration to remove intrinsic-related relocations since they are no longer used. Instead these function calls are done indirectly via a table in the `VMContext`. This means that all of this is essentially dead code!
This is the wasmtime-jit crate, which contains JIT-based execution
for wasm, using the wasm ABI defined by wasmtime-environ and the
runtime support provided by wasmtime-runtime.