Update RM48/TMS570 port to use xTaskIncrementTick in place of vTaskIncrementTick.

FreeRTOS/Source/portable/CCS/ARM_Cortex-R4/port.c

@@ -279,11 +279,11 @@ void vPortEndScheduler(void)
 	__interrupt void vPortNonPreemptiveTick( void )
 	{
 		/* clear clock interrupt flag */
-		RTI->INTFLAG = 0x00000001;
+		portRTI_INTFLAG_REG = 0x00000001;
 
 		/* Increment the tick count - this may make a delaying task ready
 		to run - but a context switch is not performed. */
-		vTaskIncrementTick();
+		xTaskIncrementTick();
 	}
 
  #else

FreeRTOS/Source/portable/CCS/ARM_Cortex-R4/portASM.asm

@@ -54,7 +54,7 @@
         .text
         .arm
         .ref vTaskSwitchContext
-        .ref vTaskIncrementTick
+        .ref xTaskIncrementTick
         .ref ulTaskHasFPUContext
 		.ref pxCurrentTCB
 
@@ -225,10 +225,11 @@ vPortPreemptiveTick:
 
         ; Increment the tick count, making any adjustments to the blocked lists
         ; that may be necessary.
-        BL      vTaskIncrementTick
+        BL      xTaskIncrementTick
 
         ; Select the next task to execute.
-        BL      vTaskSwitchContext
+        CMP	R0, #0
+        BLNE    vTaskSwitchContext
 
         ; Restore the context of the task selected to execute.
         portRESTORE_CONTEXT