We need to prepare for storage buffers having different sizes from
uniform buffers. This switches dynamic_offset_offset to have units of
bytes, the same as offset, and as a nice bonus we can more easily
combine the dynamic and non-dynamic paths in various different places.
This also entails rewriting the code that patches dynamic descriptors,
since we can no longer assume a linear mapping between indices in
dynamicOffsets and descriptor locations which the previous approach
heavily relied on.
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15288>
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