arm: socfpga: arria5: Undefine CONFIG_SPI_FLASH_USE_4K_SECTORS

Undefine CONFIG_SPI_FLASH_USE_4K_SECTORS for UBI
and UBIFS support on serial NOR flash

Signed-off-by: Chin Liang See <clsee@altera.com>
Cc: Dinh Nguyen <dinguyen@opensource.altera.com>
Cc: Dinh Nguyen <dinh.linux@gmail.com>
Cc: Pavel Machek <pavel@denx.de>
Cc: Marek Vasut <marex@denx.de>
Cc: Stefan Roese <sr@denx.de>