platform: port mcastcapture's stacktrace.c

We are switching mcastcapture to using libstacktrace instead of its own
version. Since the latter has recently been improved, I thought it makes
sense to use that version in libstacktrace.

Change-Id: I3bc3929f6dfc3a8f4bdd7d6231fd05e319d1acf4
4 files changed