Fix Visual Studio build of VulkanUnitTests

- Make VulkanUnitTests depend on SPIRV-Tools.
- Build Vulkan DLLs but don't link statically with VulkanUnitTests.
- Don't use Unicode character set.
- Statically link runtime library.
- Fix narrowing conversion from 'VkCommandBufferUsageFlagBits' to
  'VkCommandBufferUsageFlags'.

Bug swiftshader:125

Change-Id: I7dbdc25c829cc76b5e05cd57cd9f85bf2d4e0903
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/26948
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
diff --git a/tests/VulkanUnitTests/Device.cpp b/tests/VulkanUnitTests/Device.cpp
index 1fcc8b8..fd2ad95 100644
--- a/tests/VulkanUnitTests/Device.cpp
+++ b/tests/VulkanUnitTests/Device.cpp
@@ -358,7 +358,7 @@
 }
 
 VkResult Device::BeginCommandBuffer(
-		VkCommandBufferUsageFlagBits usage, VkCommandBuffer commandBuffer) const
+		VkCommandBufferUsageFlags usage, VkCommandBuffer commandBuffer) const
 {
     VkCommandBufferBeginInfo info = {
         VK_STRUCTURE_TYPE_COMMAND_BUFFER_BEGIN_INFO,  // sType