Add adjtimex

Change-Id: Ia92d35b1851e73c9f157a749dba1e98f68309a8d
Signed-off-by: Greg Hackmann <ghackmann@google.com>
diff --git a/libc/SYSCALLS.TXT b/libc/SYSCALLS.TXT
index 526b6d0..e045049 100644
--- a/libc/SYSCALLS.TXT
+++ b/libc/SYSCALLS.TXT
@@ -223,6 +223,7 @@
 int           timerfd_create(clockid_t, int)   all
 int           timerfd_settime(int, int, const struct itimerspec*, struct itimerspec*)   all
 int           timerfd_gettime(int, struct itimerspec*)   all
+int           adjtimex(struct timex*)   all
 
 # signals
 int     __sigaction:sigaction(int, const struct sigaction*, struct sigaction*)  arm,mips,x86