ARM: vexpress: Cleanup cppcheck shifting warning

Fix below warning from cppcheck tool using BIT() macro:
"Shifting signed 32-bit value by 31 bits is undefined behaviour errors"
Signed-off-by: NPhong Tran <tranmanphong@gmail.com>
Signed-off-by: NSudeep Holla <sudeep.holla@arm.com>

arch/arm/mach-vexpress/spc.c

@@ -69,7 +69,7 @@
 #define A7_PERFVAL_BASE		0xC30
 
 /* Config interface control bits */
-#define SYSCFG_START		(1 << 31)
+#define SYSCFG_START		BIT(31)
 #define SYSCFG_SCC		(6 << 20)
 #define SYSCFG_STAT		(14 << 20)
 
@@ -162,7 +162,7 @@ void ve_spc_cpu_wakeup_irq(u32 cluster, u32 cpu, bool set)
 	if (cluster >= MAX_CLUSTERS)
 		return;
 
-	mask = 1 << cpu;
+	mask = BIT(cpu);
 
 	if (!cluster_is_a15(cluster))
 		mask <<= 4;