Update to kernel headers v4.12.3.

Test: Built angler.
Change-Id: Icbcf4fac2334de8409b049ed7a3b4c24b4e98ce9
diff --git a/libc/kernel/uapi/asm-arm/asm/unistd-common.h b/libc/kernel/uapi/asm-arm/asm/unistd-common.h
index b2b6e94..c9ee555 100644
--- a/libc/kernel/uapi/asm-arm/asm/unistd-common.h
+++ b/libc/kernel/uapi/asm-arm/asm/unistd-common.h
@@ -370,4 +370,5 @@
 #define __NR_pkey_mprotect (__NR_SYSCALL_BASE + 394)
 #define __NR_pkey_alloc (__NR_SYSCALL_BASE + 395)
 #define __NR_pkey_free (__NR_SYSCALL_BASE + 396)
+#define __NR_statx (__NR_SYSCALL_BASE + 397)
 #endif