Remove Tblgen rewrite redundant native calls

[AlexandreEichenberger]

Currently, the tblgen rewrite generates redundant native calls. This is a problem as some native calls may involve significant computations (e.g. when performing constant propagation where every values in a large tensor is touched).

The pattern was as follow:

if (native-call(args)) tblgen_attrs.emplace_back(rewriter, attribute, native-call(args))

The replacement pattern compute native-call(args) once and then use it both in the if condition and the emplace_back call.

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