thermal: exynos: fix compile error in _zone_bind_cooling_device()

commit (6cd9e9f6 thermal: of: fix cooling device weights in device
tree) changed the prototype of thermal_zone_bind_cooling_device() but
did not fix up all the users.   This patch fixes up the exynos driver.

LSK Note: This patch is LSK specific because the upstream version of
the driver was later removed after being migrated to of-thermal.

Signed-off-by: Kevin Hilman <khilman@linaro.org>