Make init scripts depend on Makefile

This brings it in line with the example:
https://www.gnu.org/software/automake/manual/html_node/Scripts.html

This way, if the substitution code is changed, they should update.

Signed-off-by: Richard Laager <rlaager@wiktel.com>

etc/init.d/Makefile.am

@@ -15,7 +15,7 @@ EXTRA_DIST = \
 	$(top_srcdir)/etc/init.d/zfs-zed.in \
 	$(top_srcdir)/etc/init.d/zfs.in
 
-$(init_SCRIPTS) $(initconf_SCRIPTS) $(initcommon_SCRIPTS):%:%.in
+$(init_SCRIPTS) $(initconf_SCRIPTS) $(initcommon_SCRIPTS):%:%.in Makefile
 	-(if [ -e /etc/debian_version ]; then \
 		NFS_SRV=nfs-kernel-server; \
 	  else \