media: i2c: s5c73m3: remove support for platform data

There are no existing users of s5c73m3_platform_data in the tree, and
new users should either be using device tree, ACPI, or static device
properties, so let's remove it from the driver.

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>