net: Use Span in ReceiveMsgBytes

Summary:
Pass a data pointer and a size as span in ReceiveMsgBytes to get the benefits of a span

This is a backport of core#20056

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Differential Revision: https://reviews.bitcoinabc.org/D10813