flash: soc_flash_mcux: Convert FLASH_ERASE_BLOCK_SIZE to DT_
flash: soc_flash_mcux: Convert FLASH_ERASE_BLOCK_SIZE to DT_

Convert generic FLASH_ERASE_BLOCK_SIZE to driver specific generated
define DT_SOC_NV_FLASH_0_ERASE_BLOCK_SIZE.

Signed-off-by: Kumar Gala <a5e5248af4cd4f0ed8c515f61d40a6e2db46a66e@linaro.org>

ldts/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,finikorg/zephyr,galak/zephyr,GiulianoFranchetto/zephyr,ldts/zephyr,nashif/zephyr,galak/zephyr,explora26/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,explora26/zephyr,nashif/zephyr,Vudentz/zephyr,Vudentz/zephyr,GiulianoFranchetto/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,finikorg/zephyr,explora26/zephyr,finikorg/zephyr,GiulianoFranchetto/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,Vudentz/zephyr,finikorg/zephyr,finikorg/zephyr,ldts/zephyr,nashif/zephyr,ldts/zephyr,GiulianoFranchetto/zephyr,galak/zephyr,Vudentz/zephyr,explora26/zephyr,explora26/zephyr