anv: add assert for isl_mod_info in choose_isl_tiling_flags

CID: 1457859
Signed-off-by: Tapani Pälli <tapani.palli@intel.com>
Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Reviewed-by: Eric Engestrom <eric@engestrom.ch>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3469>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3469>

src/intel/vulkan/anv_image.c

@@ -112,6 +112,7 @@ choose_isl_tiling_flags(const struct anv_image_create_info *anv_info,
       flags = ISL_TILING_LINEAR_BIT;
       break;
    case VK_IMAGE_TILING_DRM_FORMAT_MODIFIER_EXT:
+      assert(isl_mod_info);
       flags = 1 << isl_mod_info->tiling;
    }