timer: Move sys_alarm from timer.c to itimer.c

Move the only user of alarm_setitimer to itimer.c where it is defined.
This allows for making alarm_setitimer static, and dropping it from the
build when __ARCH_WANT_SYS_ALARM is not defined.

Signed-off-by: Nicolas Pitre <nico@linaro.org>
Acked-by: John Stultz <john.stultz@linaro.org>
Cc: Paul Bolle <pebolle@tiscali.nl>
Cc: linux-kbuild@vger.kernel.org
Cc: netdev@vger.kernel.org
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Michal Marek <mmarek@suse.com>
Cc: Edward Cree <ecree@solarflare.com>
Link: http://lkml.kernel.org/r/1478841010-28605-5-git-send-email-nicolas.pitre@linaro.org
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

diff --git a/kernel/time/itimer.c b/kernel/time/itimer.c
index 1d5c720..2b9f45b 100644
--- a/kernel/time/itimer.c
+++ b/kernel/time/itimer.c
@@ -238,6 +238,8 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
 	return 0;
 }
 
+#ifdef __ARCH_WANT_SYS_ALARM
+
 /**
  * alarm_setitimer - set alarm in seconds
  *
@@ -250,7 +252,7 @@ int do_setitimer(int which, struct itimerval *value, struct itimerval *ovalue)
  * On 32 bit machines the seconds value is limited to (INT_MAX/2) to avoid
  * negative timeval settings which would cause immediate expiry.
  */
-unsigned int alarm_setitimer(unsigned int seconds)
+static unsigned int alarm_setitimer(unsigned int seconds)
 {
 	struct itimerval it_new, it_old;
 
@@ -275,6 +277,17 @@ unsigned int alarm_setitimer(unsigned int seconds)
 	return it_old.it_value.tv_sec;
 }
 
+/*
+ * For backwards compatibility?  This can be done in libc so Alpha
+ * and all newer ports shouldn't need it.
+ */
+SYSCALL_DEFINE1(alarm, unsigned int, seconds)
+{
+	return alarm_setitimer(seconds);
+}
+
+#endif
+
 SYSCALL_DEFINE3(setitimer, int, which, struct itimerval __user *, value,
 		struct itimerval __user *, ovalue)
 {