Update to v5.0 kernel headers.

Test: Builds and boots on taimen.
Change-Id: I13843bf1ab30ea89a50852adc88f2cba8401bded
diff --git a/libc/kernel/uapi/asm-arm64/asm/hwcap.h b/libc/kernel/uapi/asm-arm64/asm/hwcap.h
index 8f50b1d..44853a4 100644
--- a/libc/kernel/uapi/asm-arm64/asm/hwcap.h
+++ b/libc/kernel/uapi/asm-arm64/asm/hwcap.h
@@ -47,4 +47,7 @@
 #define HWCAP_ILRCPC (1 << 26)
 #define HWCAP_FLAGM (1 << 27)
 #define HWCAP_SSBS (1 << 28)
+#define HWCAP_SB (1 << 29)
+#define HWCAP_PACA (1 << 30)
+#define HWCAP_PACG (1UL << 31)
 #endif