[bsp/hifive1]Fixed symbol error in interrupt.c

Note that the symbol ';;' is wrong in 'return (rt_uint32_t)PLIC_claim_interrupt(&g_plic);;',
so that ';;' should been replaced with ';'.

bsp/hifive1/drivers/interrupt.c

@@ -93,7 +93,7 @@ void rt_hw_interrupt_init(void)
 
 rt_uint32_t rt_hw_interrupt_get_active(rt_uint32_t fiq_irq)
 {
-    return (rt_uint32_t)PLIC_claim_interrupt(&g_plic);;
+    return (rt_uint32_t)PLIC_claim_interrupt(&g_plic);
 }
 
 void rt_hw_interrupt_ack(rt_uint32_t fiq_irq, rt_uint32_t id)