llvmpipe: Fix variable name.

Fix warning reported by Coverity Scan.

Unused value (UNUSED_VALUE)
assigned_value: Assigning value from res->nr_samples to
jit_tex->sample_stride here, but that stored value is overwritten before
it can be used.

Fixes: 2e5cddacf7 ("llvmpipe: add num_samples/sample_stride support to jit textures")
Closes: https://gitlab.freedesktop.org/mesa/mesa/-/issues/3022
Signed-off-by: Vinson Lee <vlee@freedesktop.org>
Reviewed-by: Roland Scheidegger <sroland@vmware.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/5179>

src/gallium/drivers/llvmpipe/lp_setup.c

@@ -1014,7 +1014,7 @@ lp_setup_set_fragment_sampler_views(struct lp_setup_context *setup,
             jit_tex->height = res->height0;
             jit_tex->depth = res->depth0;
             jit_tex->first_level = jit_tex->last_level = 0;
-            jit_tex->sample_stride = res->nr_samples;
+            jit_tex->num_samples = res->nr_samples;
             jit_tex->sample_stride = 0;
             assert(jit_tex->base);
          }