GPU Vulkan: set correct destination usage mode for storage buffer read/write bindings (#13009)

src/gpu/vulkan/SDL_gpu_vulkan.c

@@ -8157,7 +8157,7 @@ static void VULKAN_BeginComputePass(
             vulkanCommandBuffer,
             bufferContainer,
             storageBufferBindings[i].cycle,
-            VULKAN_BUFFER_USAGE_MODE_COMPUTE_STORAGE_READ);
+            VULKAN_BUFFER_USAGE_MODE_COMPUTE_STORAGE_READ_WRITE);
 
         vulkanCommandBuffer->readWriteComputeStorageBuffers[i] = buffer;