devel/fstrm: Upgrade to 0.6.1

• fstrm_capture: ignore SIGPIPE, which will cause the interrupted connections to generate an EPIPE instead.
• Fix truncation in snprintf calls in argument processing.
• fstrm_capture: Fix output printf format.

PR: 255228
Tested by: freebsd@dns.company
Approved by: freebsd@dns.company (maintainer)
Sponsored by: Farsight Security, Inc.