ARM: EXYNOS: add support get_core_count() for EXYNOS5250

The EXYNOS5250 has two Cortex-A15 cores and there's no
need to call scu_enable() in platform_smp_prepare_cpus()
because Cortex-A15 has no regarding scu register which
can be used for getting number of cores.
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

arch/arm/mach-exynos/platsmp.c

@@ -166,7 +166,10 @@ void __init smp_init_cpus(void)
 	void __iomem *scu_base = scu_base_addr();
 	unsigned int i, ncores;
 
-	ncores = scu_base ? scu_get_core_count(scu_base) : 1;
+	if (soc_is_exynos5250())
+		ncores = 2;
+	else
+		ncores = scu_base ? scu_get_core_count(scu_base) : 1;
 
 	/* sanity check */
 	if (ncores > nr_cpu_ids) {
@@ -183,8 +186,8 @@ void __init smp_init_cpus(void)
 
 void __init platform_smp_prepare_cpus(unsigned int max_cpus)
 {
-
-	scu_enable(scu_base_addr());
+	if (!soc_is_exynos5250())
+		scu_enable(scu_base_addr());
 
 	/*
 	 * Write the address of secondary startup into the