Add a GPIO 1-wire bus master driver. The driver used the GPIO API to
control the wire and the GPIO pin can be specified using platform data
similar to i2c-gpio. The driver was tested with AT91SAM9260 + DS2401.
Signed-off-by: Ville Syrjala
Cc: Evgeniy Polyakov
Cc: David Brownell
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds