[TRT EP] Fix ProviderOptions functions (#17567)
### Description
When trying to use the TRT EP option trt_extra_plugin_lib_paths I
noticed that my custom op library was not being loaded by the EP. After
some digging I found that code was missing to update this option when
UpdateTensorRTProviderOptions() is used to set it.
At the same time I noticed that char arrays were allocated in that
function and wondered where they are de-allocated. When I found it was
done in ReleaseTensorRTProviderOptions(), I noticed that a few
de-allocations were missing.
### Motivation and Context
This PR fixes the problems described above.
