Fix autoconf variable substitution in init scripts.

Change the variable substitution in the init script templates
according to the method described in the Autoconf manual;
Chapter 4.7.2: Installation Directory Variables.

Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov>

etc/init.d/Makefile.am

@@ -1,5 +1,22 @@
-EXTRA_DIST = zfs.fedora zfs.gentoo zfs.lsb zfs.lunar zfs.redhat zfs.arch
+initdir = $(DEFAULT_INIT_DIR)
+init_SCRIPTS = zfs
 
-install-data-local:
-	@instdest=$(DESTDIR)$(DEFAULT_INIT_DIR)/zfs; \
-	$(INSTALL) -TD zfs.$(DEFAULT_INIT_SCRIPT) $$instdest
+EXTRA_DIST = \
+	$(top_srcdir)/etc/init.d/zfs.fedora.in \
+	$(top_srcdir)/etc/init.d/zfs.gentoo.in \
+	$(top_srcdir)/etc/init.d/zfs.lsb.in \
+	$(top_srcdir)/etc/init.d/zfs.lunar.in \
+	$(top_srcdir)/etc/init.d/zfs.redhat.in \
+	$(top_srcdir)/etc/init.d/zfs.arch.in
+
+$(init_SCRIPTS):
+	-$(SED) -e 's,@bindir\@,$(bindir),g' \
+		-e 's,@sbindir\@,$(sbindir),g' \
+		-e 's,@udevdir\@,$(udevdir),g' \
+		-e 's,@udevruledir\@,$(udevruledir),g' \
+		-e 's,@sysconfdir\@,$(sysconfdir),g' \
+		-e 's,@initdir\@,$(initdir),g' \
+		'zfs.$(DEFAULT_INIT_SCRIPT).in' >'$@'
+
+distclean-local::
+	-$(RM) $(init_SCRIPTS)