Fix test build failures.
Ensure all binaries go into libdrm-tests [RB]
(From OE-Core rev: 018bc5121c70ff1f609d5b3406401902b7e7b2f7)
Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>