The information contained in the platform data struct is redundant.

Page size == 1 is the safe default assumed if no pagesize property is
given. The EEPROM size can be indicated to the driver using the
correct model name.

Drop the at24_platform_data entirely.
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Acked-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>