The comment is misleading and there was confusion in a bug report. In the native
case STAGING_DATADIR would be equal to the native value so there isn't any issue
but tweak the comment.
[YOCTO #12761]
(From OE-Core rev: 0fdf76305a3cb543c23d6122c523ce5c2af04a0c)
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>