x11/libX11: security update to 1.8.14

PR: 299496
Approved by: x11 (maintainer, arrowd)
Security: CVE-2026-88806
Security: CVE-2026-94283
Security: CVE-2026-94284
Security: CVE-2026-94285

Sponsored by: tipi.work

(cherry picked from commit 508d2a1b42a444e1374d322f718d5ed555ceca05)