netmap: add suite of unit tests

Import the unit tests from upstream (https://github.com/luigirizzo/netmap
ba02539859d46d33), and make them ready for use with Kyua.
There are currently 38 regression tests, which test the kernel control ABI
exposed by netmap to userspace applications:

  1: test for port info get
  2-5: tests for basic port registration
  6-9: tests for VALE
  10-11: tests for getting netmap allocator info
  12-15: tests for netmap pipes
  16: test on polling mode
  17-18: tests on options
  19-27: tests for sync-kloop subsystem
  28-39: tests for null ports
  31-38: tests for the legacy NIOCREGIF registers

Reviewed by:	ngie
MFC after:	1 week
Differential Revision:	https://reviews.freebsd.org/D18490

etc/mtree/BSD.tests.dist

@@ -760,6 +760,8 @@
             tunnel
             ..
         ..
+    netmap
+    ..
         netpfil
             pf
                 ioctl

tests/sys/Makefile

@@ -20,6 +20,7 @@ TESTS_SUBDIRS+=		mac
 TESTS_SUBDIRS+=		mqueue
 TESTS_SUBDIRS+=		netinet
 TESTS_SUBDIRS+=		netipsec
+TESTS_SUBDIRS+=		netmap
 TESTS_SUBDIRS+=		netpfil
 TESTS_SUBDIRS+=		opencrypto
 TESTS_SUBDIRS+=		posixshm

tests/sys/netmap/Makefile

@@ -0,0 +1,14 @@
+# $FreeBSD$
+
+PACKAGE=	tests
+
+TESTSDIR=	${TESTSBASE}/sys/netmap
+TEST_METADATA+=	required_user="root"
+TEST_METADATA+=	is_exclusive=true
+
+LDFLAGS+= 	-lpthread
+PLAIN_TESTS_C+=	ctrl-api-test
+
+WARNS?=		6
+
+.include <bsd.test.mk>