soc: mxrt10xx: remove forces enable boot header
soc: mxrt10xx: remove forces enable boot header

When we use a third-party or custom bootloader, there is also
need to remove the boot header. Change the select to imply,
so that the boot header can be removed by configuration when
MCUBoot is not used.

Signed-off-by: Frank Li <49244b28ad48c35f973a9a3c4ee9a34d02acfa11@163.com>

galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr,finikorg/zephyr,finikorg/zephyr,finikorg/zephyr,zephyrproject-rtos/zephyr,galak/zephyr