Detect ARMv8 CRC32 and PMULL with elf_aux_info(AT_HWCAP) on
FreeBSD/aarch64 instead of the Linux-only <asm/hwcap.h> (series 1002).
For Chromium's zlib; not submitted upstream yet.
--- third_party/zlib/BUILD.gn.orig	2026-09-29 08:00:52 UTC
+++ third_party/zlib/BUILD.gn
@@ -123,6 +123,8 @@ if (use_arm_neon_optimizations) {
     defines = [ "CRC32_ARMV8_CRC32" ]
     if (is_android) {
       defines += [ "ARMV8_OS_ANDROID" ]
+    } else if (current_os == "freebsd") {
+      defines += [ "ARMV8_OS_FREEBSD" ]
     } else if (is_linux || is_chromeos) {
       defines += [ "ARMV8_OS_LINUX" ]
     } else if (is_mac) {