Really add adjtimex(2), and add clock_adjtime(2) too.

Change-Id: I81fde2ec9fdf787bb19a784ad13df92d33a4f852
diff --git a/libc/arch-arm64/syscalls/clock_adjtime.S b/libc/arch-arm64/syscalls/clock_adjtime.S
new file mode 100644
index 0000000..c2c191e
--- /dev/null
+++ b/libc/arch-arm64/syscalls/clock_adjtime.S
@@ -0,0 +1,14 @@
+/* Generated by gensyscalls.py. Do not edit. */
+
+#include <private/bionic_asm.h>
+
+ENTRY(clock_adjtime)
+    mov     x8, __NR_clock_adjtime
+    svc     #0
+
+    cmn     x0, #(MAX_ERRNO + 1)
+    cneg    x0, x0, hi
+    b.hi    __set_errno_internal
+
+    ret
+END(clock_adjtime)