Installer suffixes are inconsistent

Quoting @messmerd from https://github.com/LMMS/lmms/pull/8521#discussion_r3847955529:

I don't really like how arm64 gets the "-arm64" suffix (specifying the architecture) but x86_64 gets the "-win64" suffix (specifying the OS). It's inconsistent.

What if we specified both the OS and architecture in the form OS-ARCH-COMPILER?

if(IS_ARM64)
	set(CPACK_PACKAGE_FILE_NAME      "${CMAKE_PROJECT_NAME}-${VERSION}-windows-arm64-${WIN_PLATFORM}")
else()
	set(CPACK_PACKAGE_FILE_NAME      "${CMAKE_PROJECT_NAME}-${VERSION}-windows-x86_64-${WIN_PLATFORM}")
endif()

This would match what Linux does (-linux-aarch64 and -linux-x86_64) as well as macOS (-mac15.7-arm64 and -mac15.7-x86_64).

(Side note: It looks like macOS isn't using the correct deployment target in its name. Also, maybe we'd want to rename "aarch64" to "arm64" on Linux?)

Originally posted by @messmerd in https://github.com/LMMS/lmms/pull/8521#discussion_r3847955529