SAM4L tickless implementation:  Bug fix and update the demo project to exercise the fix.

git-svn-id: http://svn.code.sf.net/p/freertos/code/trunk@2305 1d2547de-c912-0410-9cb9-b8ca96c0e9e2
Core kernel code:
+ Introduce xSemaphoreGenericGiveFromISR() as an optimisation when giving semaphores and mutexes from an interrupt.

Demo applications:
+ Update IntSemTest.c to provide more code coverage in xSemaphoreGenericGiveFromISR().
+ Ensure the MMU is turned on in the RZ IAR demo.  It was already on in the RZ ARM demo.


git-svn-id: http://svn.code.sf.net/p/freertos/code/trunk@2306 1d2547de-c912-0410-9cb9-b8ca96c0e9e2