PR10599 Always print modname when available (and requested).

PR10599 Always print modname when available (and requested).

* runtime/sym.c (_stp_umod_lookup): Also return vm_end if available.
  (_stp_kallsyms_lookup): Don't try to handle 32bit-on-64bit signedness,
  _stp_umod_lookup already does. If available return modname, size and
  offset.
  (_stp_print_addr): Always print modname when available (and requested).
  (_stp_symbol_snprint): Likewise.
* runtime/unwind.c (unwind): Adjust _stp_umod_lookup call.
* tapset/ucontext.stp (umodname): Likewise.