In meta-boot2qt-toradex here https://code.qt.io/cgit/yocto/meta-boot2qt-toradex.git/ there is a bbapend file (recipes-core/base-files/base-files_%.bbappend) doing this:

do_install:append() {
    # add toradex specific mount point
    cat >> ${D}${sysconfdir}/fstab <<EOF
/dev/boot-part       /boot                auto       noatime,noauto        0  0
EOF
} 

This line in fstab does nothing as /dev/boot-part does not exists, but it still creates a systemctl service under boot.mount

root@b2qt-apalis-imx8:~# systemctl status boot.mount
○ boot.mount - /boot
     Loaded: loaded (/etc/fstab; generated)
     Active: inactive (dead)
      Where: /boot
       What: /dev/boot-part
       Docs: man:fstab(5)
             man:systemd-fstab-generator(8) 

This will interfere with toradex own way of mounting /boot with the help of this script and udev-rule (https://git.toradex.com/cgit/meta-toradex-bsp-common.git/tree/recipes-core/udev/files/toradex-mount-bootpart.sh?h=scarthgap-7.x.y) as it will generate this error:

Failed to start transient mount unit: Unit boot.mount was already loaded or has a fragment file.

after removing the fstab line it works fine.

So since this line in fstab does nothing and it also breaks toradex own script, I think base-files_%.bbappend should be removed entirely