llvmpipe discarded on non-neon hw

[kwizart]

As commented in the mesa-22.2.4 rebase, there is still a need to discard the llvmpipe driver on software fallback on non-neon capable hardware.

This as shown with commit https://github.com/grate-driver/mesa/commit/4621b88ee2e0f2cdbcb76d9f14eda4922c0123f4 Without this a SIGILL is experienced when running glxgears (or glmark2).

I've tried to report at llvm that has spotted an interesting regression without fixing the SIGILL https://github.com/llvm/llvm-project/issues/59286 and reported to mesa upstream https://gitlab.freedesktop.org/mesa/mesa/-/issues/7868

[kwizart]

Fixed with https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20766

I will re-order patches on grate-22.2 in a few...