Looks like for some reason Petalinux 2019.2 doesn’t add it’s compilers to the PATH when sourcing the settings script. You can add it manually - they’re at {}/tools/xsct/gnu/microblaze/lin/bin/. Note that we don’t support 2019.2 so can’t help you with any other Petalinux issues that arise. Also I’d strongly recommend the board agnostic flow and avoiding the issue entirely.
Peter