libarchive: merge vendor bugfixes
Bugfixes:
IS #1672 and OSS-Fuzz #38766: (zip reader) fix possible out-of-bounds read in zipx_lzma_alone_init() PR #1676: (mtree reader) remove the unused variable "detected_bytes" PR #1674: (doc) fix use of At mdoc(7) macro in cpio.5
Approved by: re (gjb)
(cherry picked from commit 0c9c2eb394b4a5694bc5ea11b326f334c735c813)
(cherry picked from commit 60338b80693000ed0f9812b90ca54d35fd077cd0)