Arm backend: Add argument to list used fallback ops for run.sh (#5815)

Summary:
This make it possible to specify what non EthosU ops to include in the build from the command line when running run.sh. As run.sh supports running models specified in files the hard coded approach is incontinent.

Pull Request resolved: https://github.com/pytorch/executorch/pull/5815

Reviewed By: mergennachin

Differential Revision: D63813013

Pulled By: digantdesai

fbshipit-source-id: f5e0e0c06fa9f804336dbc06864b6c9bbc9ec8d8