fix Visual Studio build

[MomoDeve]

• fix depracted function errors which occur since Vulkan 1.2
• make validation layers optional (via LEGIT_ENABLE_DEBUGGING macro)
• add LegitProfiler as git submodule and fix related paths
• replace Vulkan SDK absolute path to $(VULKAN_SDK) environment variable (which is automatically set when installing Vulkan SDK)

[Raikiri]

Hey, thanks for this. Especially the submodule thing -- I thought I set up the dependency correctly, but people still complained that it did not fetch automatically.