[vulkan] performance_wrap test results don't match

There appear to be some incorrect results in the performance_wrap test for shared memory that need investigating:

```
HL_JIT_TARGET=host-vulkan-vk_int8-vk_int16-vk_int64-vk_float16-vk_float64-vk_v13 ./build/test/performance/performance_wrap 
wrapper(1, 0) = 90 instead of 0
wrapper(2, 0) = 180 instead of 0
wrapper(3, 0) = 270 instead of 0

```