Fix compilation when path includes spaces

[joostrijneveld]

Currently compilation of release would break when the path to stlink included spaces. There seemed to be no proper way to fix this by escaping within COMPILE_FLAGS, but since CMake 3.0 there is a COMPILE_DEFINITIONS property that handles escaping itself.

[xor-gate]

Hi @joostrijneveld, I understand your concern about this problem. Only I want people give the room to use older cmake versions. CMake 3.0 is released 3 years ago.

https://blog.kitware.com/cmake-3-0-0-available-for-download/

[joostrijneveld]

I see your concern.. It's not entirely clear to me if this strictly requires CMake 3.0 though, as I'm now also finding references to this in older CMake documentation. I'll spin up a VM and give it a test..

[xor-gate]

Most systems come with CMake 2.6 or higher. Ubuntu LTS comes with 2.6, Debian oldstable with 2.8, Debian stable with 3.0.2. And I want also support older BSDs.

[joostrijneveld]

I didn't realise 3.0 was that recent, but it appear it's not a problem after all. COMPILE_DEFINITIONS works just fine on older CMake; it's just that alternative COMPILE_DEFINITIONS_<CONFIG> was deprecated in favour of it.

To verify, I spun up a fresh Debian Wheezy VM, installed the requirements, and compiled from this branch. I'll amend my commit accordingly.

[xor-gate]

Great! This looks good.