libarchive: merge from vendor branch
Libarchive 3.7.0
Important changes (relevant to FreeBSD):
#1814 Do not account for NULL terminator when comparing with "TRAILER!!!" #1818 Add ability to produce multi-frame zstd archives #1840 year 2038 fix for pax archives on platforms with 64-bit time_t #1860 Make single bit bitfields unsigned to avoid clang 16 warning #1869 Fix FreeBSD builds with WARNS=6 #1873 bsdunzip ported to libarchive from FreeBSD #1894 read support for zstd compression in 7zip archives #1918 ARM64 filter support in 7zip archives
(cherry picked from commit e64fe029e9d3ce476e77a478318e0c3cd201ff08)