[inductor] Generate indirect_indexing checks even if optimized out (#100895)
Fixes #100831, fixes #100878
Previously `gen_assert_indirect_indexing` was only called on the index
expressions passed to `ops.load` and `ops.store` which means if the
variable is optimized out during lowering, we never generate the
assert. This instead makes `ops.indirect_indexing` eagerly generate
the assert statement, whether or not it will be used.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/100895
Approved by: https://github.com/lezcano, https://github.com/ngimel
