STLink V2 installation

In ubuntu, we have to compile the whole thing from source. Just follow taxane's github instructions.

But very importantly, in /stlink root, we have to do "make clean" before the first command "make release". otherwise, we will get:

~/stlink/src$ make release
make: *** No rule to make target 'release'.  Stop.

I guess it is a basic thing so it was not mentioned.

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Long time later...in 18.04
- install dependencies:
sudo apt-get install libusb-1.0-0-dev
sudo apt-get -y install cmake

- get code

$> git clone https://github.com/texane/stlink.git

$> cd stlink

- run make and got:
boris@boris-123:~/Softwares/Installations/stlink_texane/stlink$ make
[RELEASE]
make[1]: *** No targets specified and no makefile found.  Stop.
Makefile:27: recipe for target 'release' failed
make: *** [release] Error 2

Just make clean and it should work.

- install

$> cd build/Release && make install DESTDIR=_install

- The above should end up in build/Release
sudo cp st-flash /usr/bin
Now we are able to call st-flash anywhere in the system.

ref:
https://github.com/texane/stlink
https://github.com/texane/stlink/blob/master/doc/tutorial.md