Apologies, I almost forgot about this thread.

I had a look at your dmesg output, it seems to be incomplete. A more complete looking dmesg output should look something like this.

I'm not saying your dmesg output should be exactly like that but notice how on mine with the ticks (indicated with square brackets followed by numbers) starts with 0.000?

Anyhow, you do have a wireless interface which may mean that there's nothing wrong with the wireless chipset. Have you tried manually scanning? this may not necessarily work in managed mode (note from your pastebin from iwconfig) though you can do something like this:
If you fail to get results when you normally could before, try using something like kismet or aircrack-ng to turn your wireless interface temporarily into monitor interface and see if it picks up APs.

Now before you wonder why I am making you fork out wireless penetration testing tools, these two tools are using other ways to pick up APs from where your device is placed. If either or both of these tools could pick up APs as opposed to using the aforementioned command with iwlist wlan0 scan then retry scanning again with managed mode twice (give a few seconds in between the testing in managed mode). If it fails your chipset may have issue.

Both kismet and aircrack-ng can be obtained from extras-devel repository. kismet can be started via:
The specific tool from aircrack-ng that needs to be started (yes, aircrack-ng is actually a suite) is (as root):
Ctrl+C usually makes these programs exit as it sends an interrupt signal. To get back to managed mode do (as root):
This is not a foolproof method but it might be a way to test and see where the potential culprit maybe.

Do note that overclocking may have damaged internal components of your device. You were forewarned about the risks with overclocking, this could be one of the end result.

Edit: andreas.k: If you want to see a screwed up wireless interface (no wlan0 interface that is) in a log, have a look at this. This came from a person I was helping before that encountered this fault. No idea if the result of this was due to overclocking or what.