Integrate contrib/netbsd-tests/bin/dd into the FreeBSD test suite as

bin/dd/tests

Ensure fdescfs is mounted on /dev/fd/ for the length testcase as it's used
in validating the characters read from /dev/zero

MFC after: 2 weeks
Sponsored by: EMC / Isilon Storage Division

diff --cc bin/dd/tests/Makefile
index 0000000000000000000000000000000000000000,40fb114642cdcdea04ffc1163e2312e6c19070b1..dd04af9158871627c41da52aec026286f08615db
mode 000000,100644..100644
--- /dev/null
--- 2/bin/dd/tests/Makefile
+++ b/bin/dd/tests/Makefile
@@@ -1,0 -1,7 +1,7 @@@
 -NETBSD_ATF_TESTS_SH=  dd
+ # $FreeBSD$
+ 
++NETBSD_ATF_TESTS_SH=  dd_test
+ 
+ .include <netbsd-tests.test.mk>
+ 
+ .include <bsd.test.mk>