Indicate if the archiver supports a listing file.

Indicate if the archiver supports a listing file.

Allow the use of a file listing file if the archiver supports
it.  Add hint so that the Microsoft lib archiver uses the file
listing feature.
* libltdl/m4/libtool.m4 (_LT_PROG_AR): Indicate if the
archiver supports a listing file with the new variable
archiver_list_spec.
* libltdl/config/ltmain.m4sh: If the archiver supports
a listing file, use it when max_cmd_len is exceeded.