util/cpuinfo-aarch64: Fix build with older glibc headers
Commit 761bfe07b2c9 ("util/cpuinfo-aarch64: Detect FEAT_CSSC") started using HWCAP2_CSSC unconditionally. This macro was added to glibc's AArch64 bits/hwcap.h during the glibc 2.38 development cycle, so AArch64 hosts with older headers fail to build. Follow the existing HWCAP2_BTI handling and define HWCAP2_CSSC to zero when it is not provided by system headers. Such environments simply do not use FEAT_CSSC host optimizations. This has been tested on an Ubuntu 22.04 aarch64 host with glibc 2.35. Fixes: 761bfe07b2c9 ("util/cpuinfo-aarch64: Detect FEAT_CSSC") Signed-off-by: Tao Tang <tangtao1634@phytium.com.cn> Reviewed-by: Philippe Mathieu-Daudé <philmd@oss.qualcomm.com> Signed-off-by: Richard Henderson <richard.henderson@linaro.org> Message-ID: <20260826163753.459661-1-tangtao1634@phytium.com.cn>