I noticed the [wp77xx] section of your cfglegato output is a bit different from mine, specifically the y22-ext- is not present in your toolchain path – mine is below.
[wp77xx] Toolchain dir = /opt/swi/y22-ext-wp77xx/sysroots/x86_64-pokysdk-linux/usr/bin/arm-poky-linux-gnueabi
prefix = arm-poky-linux-gnueabi-
sysroot = /opt/swi/y22-ext-SWI9X06Y_02.18.05.00/sysroots/armv7a-neon-poky-linux-gnueabi
kernelroot = /opt/swi/y22-ext-SWI9X06Y_02.18.05.00/sysroots/armv7a-neon-poky-linux-gnueabi/usr/src/kernel
In @dfrey post here, #4 instructs to use a destination path including y22-ext- and #5 is setting up a symlink to that destination path (yours differs here). I don’t know how important (if at all) setting up the paths exactly like this are, but maybe it’s something worth considering.
What is your output for the following?
mangoh@mangoh-vm:~$ ls /opt/swi/y22-ext-wp77xx -lha
lrwxrwxrwx 1 root root 28 Sep 6 20:03 /opt/swi/y22-ext-wp77xx -> y22-ext-SWI9X06Y_02.18.05.00
mangoh@mangoh-vm:~$
Good luck.