title: Yocto external kernel module including public header
body: <p>I have written an external kernel module, very close to the hello_mod example:
  <a href="https://git.yoctoproject.org/cgit.cgi/poky/tree/meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb" rel="nofollow noreferrer">https://git.yoctoproject.org/cgit.cgi/poky/tree/meta-skeleton/recipes-kernel/hello-mod/hello-mod_0.1.bb</a></p>
  <p>However, my kernel module also provides a public header file to be provided to all code using the module. However, this header is not installed to sysroot, nor to populate_sdk.</p>
  <p>How can I achieve this? Do I have to manually add the file via FILES_${PN}_dev or modify the Makefile?</p>