m68k: split heartbeat out of timer function

The heartbeat functionality is mostly separate from the
actual timer interrupt handling, and it is only used on
five platforms.

Split it out into a separate function and call that directly
from the timer irq on those platforms.

Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Tested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
diff --git a/arch/m68k/atari/time.c b/arch/m68k/atari/time.c
index ce923a5..ce4a596 100644
--- a/arch/m68k/atari/time.c
+++ b/arch/m68k/atari/time.c
@@ -21,6 +21,7 @@
 #include <linux/export.h>
 
 #include <asm/atariints.h>
+#include <asm/machdep.h>
 
 DEFINE_SPINLOCK(rtc_lock);
 EXPORT_SYMBOL_GPL(rtc_lock);
@@ -49,6 +50,7 @@ static irqreturn_t mfp_timer_c_handler(int irq, void *dev_id)
 	} while (last_timer_count == 1);
 	clk_total += INT_TICKS;
 	timer_routine(0, NULL);
+	timer_heartbeat();
 	local_irq_restore(flags);
 
 	return IRQ_HANDLED;