No, this will not be detected as a hack, cheat or anything similar.
VAC2 only checks a list of definitions in the clients physical memory.
You can not get banned because you spin fast, since it is a usual command
coded directly into the game. But do not forget to set the clients cl_yawspeed
back to normal. The 'real' Spinhack rotates the playermodel, not the View.
This is only used when playing against other Hackers - it is supposed to make the
opponents Aimbot fail to aim at Hitboxes or Bones correctly. The bad thing is that
other clueless players who see that might type status in console and note that
players Steam ID, because they falsly think that the targeted player is really hacking.