Fix clang build.
Fix clang build.

Change-Id: If570b410ca81e2e3228b584c2e0f0178b458e2ac

CyanogenMod/android_external_vixl,xin3liang/platform_external_vixl,geekboxzone/lollipop_external_vixl,geekboxzone/lollipop_external_vixl,CyanogenMod/android_external_vixl,geekboxzone/lollipop_external_vixl,android-ia/platform_external_vixl,android-ia/platform_external_vixl,xin3liang/platform_external_vixl,geekboxzone/mmallow_external_vixl,geekboxzone/mmallow_external_vixl,android-ia/platform_external_vixl,CyanogenMod/android_external_vixl,xin3liang/platform_external_vixl,geekboxzone/mmallow_external_vixl