defconfig: drivers for EETI Egalax touchscreens (and likely others)

Alex got the EETI touchscreen to work with the BB, but had to rebuild
the evdev driver, which is why it's a module now

Also enable some other drivers which might make sense with USB touchscreens
Merge pull request #2 from mhaberler/3.8.13-bone27-xenomai

defconfig: drivers for EETI Egalax touchscreens (and likely others)