sw64: fix compile error and warning for CONFIG_SMP=n

Sunway inclusion
category: feature
bugzilla: https://gitee.com/openeuler/kernel/issues/I56OLG

--------------------------------
Signed-off-by: NGu Zitao <guzitao@wxiat.com>

arch/sw_64/kernel/process.c

@@ -52,7 +52,7 @@ void arch_cpu_idle(void)
 static void common_shutdown_1(void *generic_ptr)
 {
 	struct halt_info *how = (struct halt_info *)generic_ptr;
-	int cpuid = smp_processor_id();
+	int cpuid __maybe_unused = smp_processor_id();
 
 	/* No point in taking interrupts anymore. */
 	local_irq_disable();

arch/sw_64/kernel/time.c

@@ -4,6 +4,9 @@
 #include <linux/delay.h>
 #include <linux/time.h>
 #include <linux/clk-provider.h>
+#ifndef CONFIG_SMP
+#include <linux/clocksource.h>
+#endif
 
 #include <asm/debug.h>