[PATCH] rt2x00: Move rt2x00dev flags into enumeration

By putting the flags into a enumeration we can
make it easier maintable since we don't have to
assign numbers for each flag. This makes it easier
to insert and remove flags.

Signed-off-by: Ivo van Doorn <IvDoorn@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>