libarchive: merge from vendor branch

Libarchive 3.7.3

New features:
#1941 uudecode filter: support file name and file mode in raw mode
#1943 7-zip reader: translate Windows permissions into UNIX
permissions
#1962 zstd filter now supports the "long" write option
#2012 add trailing letter b to bsdtar(1) substitute pattern
#2031 PCRE2 support
#2054 add support for long options "--group" and "--owner" to tar(1)

Security fixes:
#2101 Fix possible vulnerability in tar error reporting introduced
in f27c173

Important bugfixes:
#1974 ISO9660: preserve the natural order of links
#2105 rar5: fix infinite loop if during rar5 decompression the last
block produced no data
#2027 xz filter: fix incorrect eof at the end of an lzip member
#2043 zip: fix end-of-data marker processing when decompressing zip
archives

PR: 278315 (exp-run)
MFC after: 1 week

MFV r361280:
Update libarchive to 3.4.3

Relevant vendor changes:
PR #1352: support negative zstd compression levels
PR #1359: improve zstd version checking
PR #1348: support RHT.security.selinux from GNU tar
PR #1357: support for archives compressed with pzstd
PR #1367: fix issues in acl tests
PR #1372: child handling cleanup
PR #1378: fix memory leak from passphrase callback

MFV r324145,324147:
Sync libarchive with vendor.

Relevant vendor changes:
PR #905: Support for Zstandard read and write filters
PR #922: Avoid overflow when reading corrupt cpio archive
Issue #935: heap-based buffer overflow in xml_data (CVE-2017-14166)
OSS-Fuzz 2936: Place a limit on the mtree line length
OSS-Fuzz 2394: Ensure that the ZIP AES extension header is large enough
OSS-Fuzz 573: Read off-by-one error in RAR archives (CVE-2017-14502)

MFC after: 1 week
Security: CVE-2017-14166, CVE-2017-14502