Add portMEMORY_BARRIER defination to fix over-optimization in xTaskResumeAll. (#1116)

Co-authored-by: owen <owen@freqchip.com>
diff --git a/portable/ThirdParty/XCC/Xtensa/portmacro.h b/portable/ThirdParty/XCC/Xtensa/portmacro.h
index d6a79b9..dced238 100644
--- a/portable/ThirdParty/XCC/Xtensa/portmacro.h
+++ b/portable/ThirdParty/XCC/Xtensa/portmacro.h
@@ -114,6 +114,7 @@
 #define portTICK_PERIOD_MS          ( ( TickType_t ) 1000 / configTICK_RATE_HZ )
 #define portBYTE_ALIGNMENT          4
 #define portNOP()                   XT_NOP()
+#define portMEMORY_BARRIER()        XT_MEMW()
 /*-----------------------------------------------------------*/
 
 /* Fine resolution time */