Common scheduler code:

- Back out changes that allow mutexes to be given from a semaphore after tests showed issues that would not be fast to fix.

Demo projects:

- Update the Microblaze Kintex 7 project and BSP to use version 2015.2 of the Xilinx SDK.

FreeRTOS/Source/queue.c

@@ -1221,9 +1221,7 @@ Queue_t * const pxQueue = ( Queue_t * ) xQueue;
 
 	/* Normally a mutex would not be given from an interrupt, especially if 
 	there is a mutex holder, as priority inheritance makes no sense for an 
-	interrupts, only tasks.  However, on occasions when it is wanted to give
-	a mutex from an interrupt, use xQueueSendFromISR() in place of
-	xSemaphoreGiveFromISR(). */
+	interrupts, only tasks. */
 	configASSERT( !( ( pxQueue->uxQueueType == queueQUEUE_IS_MUTEX ) && ( pxQueue->pxMutexHolder != NULL ) ) );
 
 	/* RTOS ports that support interrupt nesting have the concept of a maximum