arch: arc: update the ARC port

* add basic synopsys arc em processor support
* add basic arc nsim em virtual board support
* add basic arc mwdt toolchain support

Signed-off-by: Watson Zeng <zhiwei@synopsys.com>

board/ARC_NSIM_EM/BSP/Src/main.c

@@ -1,22 +1,17 @@
 #include "cmsis_os.h"
-
-#define APPLICATION_TASK_STK_SIZE       1024*64
+#include <stdio.h>
 
 extern void application_entry(void *arg);
-osThreadDef(application_entry, osPriorityNormal, 1, APPLICATION_TASK_STK_SIZE);
-
-EMBARC_WEAK void application_entry(void *arg)
-{
-    while (1) {
-        printf("This is a demo task,please use your task entry!\r\n");
-        tos_task_delay(1000);
-    }
-}
 
 int main(void)
 {
-    printf("Welcome to TencentOS tiny\r\n");
-    osKernelInitialize(); // TOS Tiny kernel initialize
-    osThreadCreate(osThread(application_entry), NULL); // Create TOS Tiny task
-    osKernelStart(); // Start TOS Tiny
+   printf("hello world\r\n");
+   printf("***I am task\r\n");
+   osKernelInitialize(); //TOS Tiny kernel initialize
+   application_entry(NULL);
+   osKernelStart(); //Start TOS Tiny
+
+   while (1)
+   {
+   }
 }