target-libpath.exp: New file defining set_ld_library_path_env_vars and restore_ld_library_path_env_vars.

	* lib/target-libpath.exp: New file defining set_ld_library_path_env_vars
	and restore_ld_library_path_env_vars.
	* g++.dg/compat/compat.exp, lib/g++.exp, lib/gcc-dg.exp,
	lib/gfortran.exp, lib/objc.exp, lib/treelang.exp: Use new procs.
	* ada/acats/run_acats (LD_LIBRARY_PATH): Add previous LD_LIBRARY_PATH
	to LD_LIBRARY_PATH.  Export LD_LIBRARY_PATH.

	* testsuite/lib/libffi-dg.exp: Use new procs in target-libpath.exp.

	* testsuite/lib/libjava.exp,
	testsuite/libjava.jacks/jacks.exp: Use new procs in target-libpath.exp.

	* testsuite/lib/libmudflap.exp: Use new procs in target-libpath.exp.

	* testsuite/lib/libstdc++.exp: Use new procs in target-libpath.exp.

From-SVN: r91137