Log Message:
libreoffice: add build fix for NetBSD/aarch64

For aarch64 on NetBSD we apply -mno-outline-atomics as one way of
getting around linking issues that otherwise occur with GCC from
pkgsrc. XXX when -current moves to GCC 12, this should be revisited.
Issue reported and fix supplied and tested by Paul Ripke on
pkgsrc-users. (Same approach already used elsewhere in pkgsrc, e.g.,
graphics/exiv2.)