spi: fsl_qspi: Update write data size for page program LUT

The write data size can be overwritten by writing to the IDATSZ
field of IPCR register. Since the driver always updates the IDATSZ
in page program operation. Set the LUT data size to 0 to align
the codes with iMX.

Signed-off-by: Ye Li <ye.li@nxp.com>