Cannot use the nts framework when build test binaries

[Revimal]

Cannot include "nts.h"

Here is the build log

== Build selftest
make[1]: Entering directory '/home/hhseo/ndrte/native/selftest'
/home/hhseo/ndrte/selftest/selftest_lfqueue.c:3:17: fatal error: nts.h: No such file or directory
compilation terminated.
/home/hhseo/ndrte/ndr-build-env/ndr.app.mk:25: recipe for target 'selftest_lfqueue.c' failed
make[1]: *** [selftest_lfqueue.c] Error 1
make[1]: Leaving directory '/home/hhseo/ndrte/native/selftest'
/home/hhseo/ndrte/ndr-build-env/ndr.mkroot.mk:35: recipe for target 'selftest' failed

[Revimal]

Merge issue to #6