Link in NetBSD's unifdef(1) tests

Skip one, is it currently fails.

contrib/netbsd-tests/usr.bin/unifdef/t_basic.sh

@@ -51,6 +51,10 @@ lastline_body() {
 	printf '#ifdef foo\n#endif\n' >input
 	atf_check -o file:input unifdef -Ubar input
 
+	# Begin FreeBSD
+	atf_skip "our version doesn't have this behavior"
+	# Endif
+
 	# Without newline after cpp directive
 	printf '#ifdef foo\n#endif' >input
 	atf_check -o file:input unifdef -Ubar input

etc/mtree/BSD.tests.dist

@@ -1064,6 +1064,8 @@
         ..
         uuencode
         ..
+        unifdef
+        ..
         uniq
         ..
         vmstat

usr.bin/unifdef/Makefile

@@ -1,8 +1,13 @@
 #	@(#)Makefile	8.1 (Berkeley) 6/6/93
 # $FreeBSD$
 
+.include <src.opts.mk>
+
 PROG=	unifdef
 SCRIPTS=unifdefall.sh
 MLINKS=	unifdef.1 unifdefall.1
 
+HAS_TESTS=
+SUBDIR.${MK_TESTS}+= tests
+
 .include <bsd.prog.mk>

usr.bin/unifdef/tests/Makefile

@@ -0,0 +1,12 @@
+# $FreeBSD$
+
+PACKAGE=	tests
+
+NETBSD_ATF_TESTS_SH=	basic_test
+
+${PACKAGE}FILES+=	d_basic.in
+${PACKAGE}FILES+=	d_basic.out
+
+.include <netbsd-tests.test.mk>
+
+.include <bsd.test.mk>