ARM: OMAP2+: free use_gptimer_clksrc variable after boot

The variable use_gptimer_clksrc is only used by two __init functions,
So we can freely free it after boot.
Signed-off-by: NOussama Ghorbel <ghorbel@pivasoftware.com>
Signed-off-by: NTony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/timer.c

@@ -361,7 +361,7 @@ static void __init omap2_gp_clockevent_init(int gptimer_id,
 
 /* Clocksource code */
 static struct omap_dm_timer clksrc;
-static bool use_gptimer_clksrc;
+static bool use_gptimer_clksrc __initdata;
 
 /*
  * clocksource