Implement read-write memory accessors for SyncReadMem (backport #3190) (#3213)

* Implement read-write memory accessors for SyncReadMem (#3190)

Adds new APIs to generate explicit read-write (rdwr) ports for a SyncReadMem, and all masked or clocked variants.
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Co-authored-by: Megan Wachs <megan@sifive.com>
(cherry picked from commit 1e6f2b4e

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* Add CompileOptions to SyncReadMem.readWrite methods

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Co-authored-by: Jared Barocsi <82000041+jared-barocsi@users.noreply.github.com>
Co-authored-by: Jack Koenig <koenig@sifive.com>
Co-authored-by: mergify[bot] <37929162+mergify[bot]@users.noreply.github.com>