sysutils/lttng-tools: fix obtaining HOST_NAME_MAX
Using sysconf(3) API lead to accidental introduction of variable length arrays
(VLA) in the port. Additionally one patch hardcoded 256 as the HOST_NAME_MAX
even though the code doesn't expect an additional byte for the terminating NULL
byte in the struct definition.
Fall back to using _POSIX_HOST_NAME_MAX as the remaining code is not ready for
introducing sysconf(3) as a patch.
Remove #ifdef FreeBSD from our patches.
Bump PORTREVISION to rebuild with the new patch.
Sponsored by: Fudo Security
Differential Revision: https://reviews.freebsd.org/D30048