rt2x00: fix rt2x00 to work with the new ralink SoC config symbols

Since v3.9-rc1 the kernel has basic support for Ralink WiSoC. The config symbols
are named slightly different than before. Fix the rt2x00 to match the new
symbols.

The commit causing this breakage is:
commit ae2b5bb6
Author: John Crispin <blogic@openwrt.org>
Date:   Sun Jan 20 22:05:30 2013 +0100
MIPS: ralink: adds Kbuild files

Signed-off-by: John Crispin <blogic@openwrt.org>
Acked-by: Gertjan van Wingerde <gwingerde@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>