automake: don't install /e/d/zfs or /e/z/zfs-functions +x
_SCRIPTS means it's made +x when installing; _DATA is made -x.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Ahelenia Ziemiańska <nabijaczleweli@nabijaczleweli.xyz>
Closes #13496
Closes #13503