a0a3d4728a Fix deprecation notice (Tobin C. Harding)
Pull request description:
Recently we deprecated the `segwit_signature_hash` function but during development the deprecation notice got stale.
Fix deprecation notice to use the actual function names.
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Tree-SHA512: d84941b605c5bc6ceab75cd60eb820c1d2c16fcd1431dc3927dc22d79886d3de26fd796fab92d97e7f8d567eab0b5a1987303107720524e7b648b1168541a2ed