Rename nanokernel files

Makes various nanokernel file names more accurately reflect their
actual roles, and improves consistency with other naming conventions.

Change-Id: Ibea5a66a8d66c4e41810d6b3d70b4c459a3848a8
Signed-off-by: Allan Stephens <allan.stephens@windriver.com>

kernel/nanokernel/nano_context.c

@@ -1,4 +1,4 @@
-/* nanocontextentry.c - VxMicro nanokernel context entry/exit logic */
+/* nanokernel context support */
 
 /*
  * Copyright (c) 2010-2014 Wind River Systems, Inc.
@@ -32,8 +32,8 @@
 
 /*
 DESCRIPTION
-This module provides a wrapper around a context entry point for starting and
-ending the context, be it a task or a fiber.
+This module provides general purpose context support, with applies to both
+tasks or fibers.
 */
 
 #include <toolchain.h>

kernel/nanokernel/nano_fiber.c

@@ -1,4 +1,4 @@
-/* nanofiber.c - VxMicro nanokernel fiber support primitives */
+/* nanokernel fiber support primitives */
 
 /*
  * Copyright (c) 2010-2014 Wind River Systems, Inc.

kernel/nanokernel/nano_fifo.c

@@ -32,9 +32,9 @@
 
 /*
 DESCRIPTION
-This module provides the VxMicro nanokernel (aka system-level)
-'multiple-waiter fifo' (fifo) implementation.  This module provides the
-backing implementation for the following API:
+This module provides the VxMicro nanokernel (aka system-level) 'fifo' 
+implementation. This module provides the backing implementation for the
+following APIs:
 
    nano_fifo_init
    nano_fiber_fifo_put, nano_task_fifo_put, nano_isr_fifo_put

kernel/nanokernel/nano_init.c

@@ -1,4 +1,4 @@
-/* nanoinit.c - VxMicro nanokernel initialization module */
+/* nanokernel initialization module */
 
 /*
  * Copyright (c) 2010-2014 Wind River Systems, Inc.

kernel/nanokernel/nano_sys_clock.c

@@ -1,4 +1,4 @@
-/* nanotime.c - time tracking for nanokernel-only systems */
+/* system clock support for nanokernel-only systems */
 
 /*
  * Copyright (c) 1997-2015 Wind River Systems, Inc.