ptest-runner: pass libdir to DEFAULT_DIRECTORY when compiling
Ptest data are installed to PTEST_PATH ?= "${libdir}/${BPN}/ptest".
When libdir isn't "/usr/lib", it will cause "No ptests found" error
when running "ptest-runner" command. Here pass libdir to
DEFAULT_DIRECTORY when compiling to avoid that error.
Need update ptest-runner source code to get the new commit:
<ptest-runner: make DEFAULT_DIRECTORY be able to be defined when compiling>
Signed-off-by: Li Zhou <li.zhou@windriver.com> Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>