zink: Store zink_vertex_elements_hw_state::b.strides by binding id

zink: Store zink_vertex_elements_hw_state::b.strides by binding id

Currently, we store strides by vertex buffer id, which means that we have
to map the binding index to the vertex buffer index every time we want to
get a stride for a given binding. This also creates an order mismatch when
we pass strides directly to CmdBindVertexBuffers2EXT. Instead of converting
strides for CmdBindVertexBuffers2EXT too, we can just store strides by
binding id, and drop the mapping in other places.

Fixes: 76725452 ("gallium: move vertex stride to CSO")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/9817
Signed-off-by: Sviatoslav Peleshko <sviatoslav.peleshko@globallogic.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/25305>