* lib/ld-lib.exp (run_ld_link_tests): Handle sources from other
directories.
(run_ld_link_exec_tests): Likewise.
(run_cc_link_tests): Likewise.
* ld-elf/comm-data1.sd: New test.
* ld-elf/comm-data1.s: Source for the new test.
* ld-elf/comm-data2.sd: New test.
* ld-elf/comm-data2.rd: Likewise.
* ld-elf/comm-data2.xd: Likewise.
* ld-elf/comm-data2.s: Source for the new tests.
* ld-elf/comm-data.exp: New file.
* ld-mips-elf/comm-data.exp: Likewise.
