Update to kernel headers v4.12.3.

Test: Built angler.
Change-Id: Icbcf4fac2334de8409b049ed7a3b4c24b4e98ce9
diff --git a/libc/kernel/uapi/asm-x86/asm/unistd_32.h b/libc/kernel/uapi/asm-x86/asm/unistd_32.h
index 184c230..0038efb 100644
--- a/libc/kernel/uapi/asm-x86/asm/unistd_32.h
+++ b/libc/kernel/uapi/asm-x86/asm/unistd_32.h
@@ -397,4 +397,6 @@
 #define __NR_pkey_mprotect 380
 #define __NR_pkey_alloc 381
 #define __NR_pkey_free 382
+#define __NR_statx 383
+#define __NR_arch_prctl 384
 #endif