ARM: SAMSUNG: Add GPIO configuration for a range of pins

Add s3c_gpio_cfgpin_range() to configure a range of pins to the given
value. This is useful for a number of blocks where the pins are in order
and saves multiple calls to s3c_gpio_cfgpin().

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>