HGQ QMHA and QLinformer support for oneAPI

[laurilaatu]

Description

This PR adds the required changes to enable QMHA/QLinformer in oneAPI.
Requires parsing softmax tables from HGQ and support for multidim softmax.

Type of change

• New feature (non-breaking change which adds functionality)

Tests

Test Configuration:

Checklist

• I have read the guidelines for contributing.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have installed and run pre-commit on the files I edited or added.
• I have added tests that prove my fix is effective or that my feature works.

[jmitrevs]

How are the names of tables associated with the layers? Is it now per-instance?

[jmitrevs]

This is a logic change. Before it took the upper bits. Does it now assume that the table size is always the same as the width of the value? If so, I guess it must be reinforced somewhere. Are we sure we want this?

[jmitrevs]

I see the logic is unchanged for Vivado and libero, so I am hesitant to have this change.

[jmitrevs]

table_name and table_size have very different meanings. Maybe table_name_size or something like that would read better?

[jmitrevs]

I assume this also needs changes in nnet_activation_stream.h, at least to consistently use the types.

[jmitrevs]

Tests should be written (or hgq tests enabled) to show that this works as expected.

[jmitrevs]

Also consider the libero backend for how tables are created. We may want to unify the methods. oneAPI followed the Quartus style of LUTs, which is quite old.

[jmitrevs]

Scratch that about the Libero backend. Apparently it's just cut and paste code that has not been used or tested. So overall, I think this is fine other than potentially the softmax_stable_idx_from_real_val change, which should be checked. And also there is the need to update the streaming side to use the same constants.