clocksource/drivers/timer-ti-dm: Make omap_dm_timer_set_load_start() static

Fix sparse warning:

drivers/clocksource/timer-ti-dm.c:589:5: warning:
 symbol 'omap_dm_timer_set_load_start' was not declared. Should it be static?
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: <daniel.lezcano@linaro.org>
Link: https://lkml.kernel.org/r/20190322144302.6704-1-yuehaibing@huawei.com

drivers/clocksource/timer-ti-dm.c

@@ -586,8 +586,8 @@ static int omap_dm_timer_set_load(struct omap_dm_timer *timer, int autoreload,
 }
 
 /* Optimized set_load which removes costly spin wait in timer_start */
-int omap_dm_timer_set_load_start(struct omap_dm_timer *timer, int autoreload,
-                            unsigned int load)
+static int omap_dm_timer_set_load_start(struct omap_dm_timer *timer,
+					int autoreload, unsigned int load)
 {
 	u32 l;