To change the kernel install directory (something other than /boot), from meta/classes/kernel.bbclass it seems that the variable KERNEL_IMAGEDEST needs to be modified.

But setting 'KERNEL_IMAGEDEST="kernel"' does not change anything and the kernel is still placed in /boot while I was expecting bzImage to be in /kernel.

Setting 'KERNEL_IMAGEDEST=""' (empty string to get /bzImage) causes QA errors:

WARNING: linux-yocto-5.2.17+gitAUTOINC+b867b78b50_255a750d28-r0 do_package: QA Issue: FILES variable for package kernel-devicetree contains '//' which is invalid. Attempting to fix this but you should correct the metadata.
 [files-invalid]
WARNING: linux-yocto-5.2.17+gitAUTOINC+b867b78b50_255a750d28-r0 do_package: QA Issue: FILES variable for package kernel-image-bzimage contains '//' which is invalid. Attempting to fix this but you should correct the metadata.
 [files-invalid]
ERROR: linux-yocto-5.2.17+gitAUTOINC+b867b78b50_255a750d28-r0 do_package: QA Issue: linux-yocto: Files/directories were installed but not shipped in any package:
  /bzImage
  /bzImage-5.2.17-yocto-standard
Please set FILES such that these items are packaged. Alternatively if they are unneeded, avoid installing them or delete them within do_install.
linux-yocto: 2 installed and not shipped files. [installed-vs-shipped]
ERROR: linux-yocto-5.2.17+gitAUTOINC+b867b78b50_255a750d28-r0 do_package: Fatal QA errors found, failing task.
ERROR: Logfile of failure stored in: /mnt/data/pheno/yocto/poky-master/build/tmp/work/qemux86_64-poky-linux/linux-yocto/5.2.17+gitAUTOINC+b867b78b50_255a750d28-r0/temp/log.do_package.1974
ERROR: Task (/mnt/data/pheno/yocto/poky-master/meta/recipes-kernel/linux/linux-yocto_5.2.bb:do_package) failed with exit code '1'