libubox: update to Git HEAD (2026-05-03)

libubox: update to Git HEAD (2026-05-03)

895f92164b66 uloop: add ULOOP_PRIORITY support for EPOLLPRI events
f9b1f3ff17ba uloop: revert my flag changes from the ULOOP_PRIORITY change
2982bfb1c325 blob: fix wrong type for realloc result in blob_buffer_grow()
78c20f6c8579 json_script: convert recursive __json_script_file_free() to iterative
e7c13bf8cbca usock: fix off-by-one in nanosecond normalization in poll_restart()
68b3f1588de4 uloop: usock: add error checking for fcntl and remove duplicate include
03821f942c49 uloop: fix undefined behavior in signal bit operations for signals > 32
e6e6fd83e26d blobmsg: fix policy name length overflow and add bounds check in blobmsg_parse()
d30b9cc1a02d usock: fix integer overflow in timeout calculations
406e342bb900 udebug: fix double off-by-one in udebug_entry_vprintf()
700eca0bac66 blobmsg_json: fix integer overflow in blobmsg_puts()
6351fe552162 blobmsg_json: floor strbuf size and tighten the post-format guard
58b6543f1b25 blobmsg: fix unsigned integer overflow in blobmsg_alloc_string_buffer()
d7a3ae699df0 blobmsg: use correct byte-order macro when setting BLOB_ATTR_EXTENDED
23c6618a5b90 blobmsg_json: fix double format string to avoid truncation and data loss
1edf1d704e76 jshn: fix integer overflow and type confusion in jshn_parse_file
9b488010c4a7 utils: fix integer overflow in __calloc_a()
40a87f734b94 blob: fix integer overflow in buffer growth functions
02fccb465651 blob: use size_t for blob_memdup() length
0fa612ca08f7 json_script: avoid alloca() on attacker-controlled pattern length
8c9862b6921b blobmsg: fix integer overflow in blobmsg_realloc_string_buffer()
5fbef5bb94fb ustream: avoid INT_MAX overflow on malloc in ustream_vprintf()
1501e60e5554 md5: detect read errors in md5sum() instead of returning a bogus hash

Link: https://github.com/openwrt/openwrt/pull/23212
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>