Don't build libctf tests in source dir

Running the libctf testsuite currently leaves big-struct-ctf.o in
libctf/testsuite/libctf-lookup/.

It ought to be possible to make the binutils source dir read-only,
and putting compiler output in the source dir leads to interesting
effects when testing multiple binutils targets in parallel.

	* lib/ctf-lib.exp (run_lookup_test): For "link: objects" compile
	objects in tmpdir.
1 file changed