[lantiq] ACMP252: fix USB-enable GPIO and use default PCI configuration for now

[lantiq] ACMP252: fix USB-enable GPIO and use default PCI configuration for now

EEPROM is an actial serial EEPROM on the WiFi module, therefore we can remove
ralink_eep from the dts.
USB power-enable GPIO turned out to be GPIO #3 (found via probing/brute-force).
PCI works with default settings as long as the vendor bootloader is used.

Signed-off-by: Daniel Golle <dgolle@allnet.de>
git-svn-id: svn://svn.openwrt.org/openwrt/trunk@36030 3c298f89-4303-0410-b956-a3cf2f4a3e73