nir/loop_analyze: skip if basis/limit/comparison is vector

nir/loop_analyze: skip if basis/limit/comparison is vector

Replacement in try_eval_const_alu() doesn't work because the replacements
are always scalar. The callers also always give a scalar dest.

This is encountered when compiling a Redout shader under ASan.

Signed-off-by: Rhys Perry <pendingchaos02@gmail.com>
Acked-by: Timothy Arceri <tarceri@itsqueeze.com>
Fixes: bc170e895f38 ("nir/loop_analyze: Use try_eval_const_alu and induction variable basis info")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/26225>
(cherry picked from commit 796058841378c4d5e04ff8b5cbe5adef5aae326a)