The various rt2x00 drivers use different methods to name the different
GPIO register fields indicating the GPIO pin value and the fields
indicating the direction.
Start using a unified naming scheme for the GPIO register fields:
	- <csr>_VAL<x> for fields indicating the GPIO pin value.
	- <csr>_DIR<x> for fields indicating the GPIO pin direction.
Signed-off-by: Gertjan van Wingerde <gwingerde@gmail.com>
Acked-by: Ivo Van Doorn <ivdoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>