build: CMakeLists.txt cleanup

A cleanup of the CMake file in this repo,
for consistency with similar effort in other Vulkan repos.

clarify setting Windows install prefix if needed

project() : NONE = this project has no language toolchain requirement.

update .cmake-format.py 0.4.1

reformat using cmake-format 0.4.1

Change-Id: Ic64b335676eb6b8bd8ffd1b0d8c5468a4239287c