riscv/riscv_copystate.c: Remove riscv_copystate.c as it is not used anymore

I keep getting confused by this function until I remember again that it is
not used any more. Let's just get rid of it.

arch/risc-v/src/common/Make.defs

@@ -28,7 +28,7 @@ CMN_ASRCS += riscv_saveusercontext.S
 
 # Specify C code within the common directory to be included
 CMN_CSRCS += riscv_initialize.c riscv_swint.c riscv_mtimer.c
-CMN_CSRCS += riscv_allocateheap.c riscv_createstack.c riscv_copystate.c
+CMN_CSRCS += riscv_allocateheap.c riscv_createstack.c
 CMN_CSRCS += riscv_cpuidlestack.c riscv_doirq.c riscv_exit.c riscv_exception.c
 CMN_CSRCS += riscv_getnewintctx.c riscv_getintstack.c riscv_initialstate.c
 CMN_CSRCS += riscv_idle.c riscv_modifyreg32.c riscv_nputs.c riscv_releasestack.c

arch/risc-v/src/common/riscv_copystate.c

@@ -1,72 +0,0 @@
-/****************************************************************************
- * arch/risc-v/src/common/riscv_copystate.c
- *
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements.  See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.  The
- * ASF licenses this file to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance with the
- * License.  You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
- * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
- * License for the specific language governing permissions and limitations
- * under the License.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <nuttx/config.h>
-
-#include <stdint.h>
-#include <arch/irq.h>
-
-#include "riscv_internal.h"
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: riscv_copystate
- ****************************************************************************/
-
-/* A little faster than most memcpy's */
-
-void riscv_copystate(uintptr_t *dest, uintptr_t *src)
-{
-  int i;
-
-  /* In the RISC-V model, the state is copied from the stack to the TCB,
-   * but only a reference is passed to get the state from the TCB.  So the
-   * following check avoids copying the TCB save area onto itself:
-   */
-
-  if (src != dest)
-    {
-      /* save integer registers first */
-
-      for (i = 0; i < XCPTCONTEXT_REGS; i++)
-        {
-          *dest++ = *src++;
-        }
-    }
-}

arch/risc-v/src/common/riscv_internal.h

@@ -195,8 +195,6 @@ void riscv_addregion(void);
 
 void riscv_ack_irq(int irq);
 
-void riscv_copystate(uintptr_t *dest, uintptr_t *src);
-
 void riscv_sigdeliver(void);
 int riscv_swint(int irq, void *context, void *arg);
 uintptr_t riscv_get_newintctx(void);