Fixing installation of Kyuafiles

[Simon J. Gerraty]

>The bin/sh and bin/test tests are broken because they cannot be run as root,
>yet the testing machines are currently running stuff as root.  This is easy
>to fix by adding a require_user="unprivileged" property to the tests.
>
>I was going to fix this by adding manually-crafted Kyuafile files that do
>the above in bin/sh/tests/ and bin/test/tests/ and setting KYUAFILE=yes in
>the corresponding Makefile files... but unfortunately that does not work
>with NO_CLEAN builds.

is the issue limited to just those dirs?

>The problem is that bsd.test.mk generates Kyuafile files in the obj directory
>and setting KYUAFILE=yes means that make will _still_ see the Kyuafile in the
>obj directory and not the one that just appeared in src.
>
>Does the attached patch seem reasonable to prevent this in the future?

This seems a reasonable change.