Turkey should like the Kurds getting their own place because they can all return home and out of Turkey and Iran.
You should look at the
wiki entry for Kurdistan to see why that wouldn't work. There is no "returning" to Kurdistan, since the majority of it is located in present-day Turkey. The Kurds have existed in that region for at least 5000 years (they're not Arab or Persian), so they're not going to leave willingly.
Turkey's fear is that the Turkish Kurds, upon seeing the southern third of Kurdistan freed, will revolt to unify the Kurdish nation. Given the long running Kurdish rebellion in Turkey, it's not a misplaced fear.