Exclude the "tools" from building and installing.

--- bin/Makefile.am.orig	2021-09-17 07:10:48 UTC
+++ bin/Makefile.am
@@ -1 +1 @@
-SUBDIRS = named rndc dig delv dnssec tools nsupdate check confgen tests plugins
+SUBDIRS = named rndc tools check confgen tests plugins
--- bin/tools/Makefile.am.orig	2021-09-17 07:10:48 UTC
+++ bin/tools/Makefile.am
@@ -9,11 +9,7 @@ LDADD +=			\
 	$(LIBISC_LIBS)
 
 bin_PROGRAMS =			\
-	arpaname		\
-	mdig			\
-	named-journalprint	\
-	named-rrchecker		\
-	nsec3hash
+	named-journalprint
 
 arpaname_LDADD =		\
 	$(LIBISC_LIBS)