[DynInst_API:] [dyninst/dyninst] 89e278: Fixed nullptr issues in dyninstAPI/src/mapped_obje...

["Jonathan R. Madsen" <noreply@xxxxxxxxxx>]

  Branch: refs/heads/master
  Home:   https://github.com/dyninst/dyninst
  Commit: 89e2782a1ffa784b9a022f7eefb8ad3e4bba87b6
      https://github.com/dyninst/dyninst/commit/89e2782a1ffa784b9a022f7eefb8ad3e4bba87b6
  Author: Jonathan R. Madsen <jrmadsen@xxxxxxxxxxxxxxxxxxxxxxxx>
  Date:   2023-02-09 (Thu, 09 Feb 2023)

  Changed paths:
    M dyninstAPI/src/mapped_object.C

  Log Message:
  -----------
  Fixed nullptr issues in dyninstAPI/src/mapped_object.C (#1361)

- checking whether std::string::c_str() == 0 is pointless because std::string cannot be constructed from a nullptr. use std::string::empty()
- add nullptr checks in find*Vector* functions