bsps/erc32: Add missing Doxygen headers

This adds missing Doxygen @file headers to several files in the erc32
BSP to improve documentation categorization.

bsps/sparc/erc32/btimer/btimer.c

@@ -1,10 +1,17 @@
 /* SPDX-License-Identifier: GPL-2.0+-with-RTEMS-exception */
 
-/*  timer.c
+/**
+ *  @file
+ *
+ *  @ingroup RTEMSBSPsSPARCERC32
+ *
+ *  @brief This file contains the Benchmark Timer support for the ERC32 BSP.
  *
  *  This file implements a benchmark timer using the General Purpose Timer on
  *  the MEC.
- *
+ */
+
+/*
  *  COPYRIGHT (c) 1989-1999.
  *  On-Line Applications Research Corporation (OAR).
  *

bsps/sparc/erc32/start/bspdelay.c

@@ -1,7 +1,11 @@
 /* SPDX-License-Identifier: GPL-2.0+-with-RTEMS-exception */
 
-/*
- *  ERC32 BSP Delay Method
+/**
+ * @file
+ *
+ * @ingroup RTEMSBSPsSPARCERC32
+ *
+ * @brief This file contains the implementation of the delay mechanisms for ERC32.
  */
 
 /*

bsps/sparc/erc32/start/bspidle.c

@@ -1,8 +1,14 @@
 /* SPDX-License-Identifier: GPL-2.0+-with-RTEMS-exception */
 
-/*
- *  ERC32 Idle Thread with power-down function
+/**
+ * @file
  *
+ * @ingroup RTEMSBSPsSPARCERC32
+ *
+ * @brief This file contains the idle thread with power-down function.
+ */
+
+/*
  *  COPYRIGHT (c) 1989-2009.
  *  On-Line Applications Research Corporation (OAR).
  *

bsps/sparc/erc32/start/bspsmp.c

@@ -1,5 +1,13 @@
 /* SPDX-License-Identifier: BSD-2-Clause */
 
+/**
+ * @file
+ *
+ * @ingroup RTEMSBSPsSPARCERC32
+ *
+ * @brief This file contains the Symmetric Multiprocessing (SMP) support for ERC32.
+ */
+
 /*
  * Copyright (C) 2019 embedded brains GmbH & Co. KG
  *

bsps/sparc/erc32/start/bspstart.c

@@ -1,6 +1,13 @@
 /* SPDX-License-Identifier: BSD-2-Clause */
 
-/*  Installs the BSP pre-driver hook
+/**
+ * @file
+ *
+ * @ingroup RTEMSBSPsSPARCERC32
+ *
+ * @brief This file contains the shared BSP startup code for ERC32.
+ *
+ * Installs the BSP pre-driver hook.
  */
 
 /*

bsps/sparc/erc32/start/erc32mec.c

@@ -1,8 +1,16 @@
 /* SPDX-License-Identifier: GPL-2.0+-with-RTEMS-exception */
 
-/*
- *  Put this variable in a separate file so it is only linked in when needed.
+/**
+ * @file
  *
+ * @ingroup RTEMSBSPsSPARCERC32
+ *
+ * @brief This file contains the ERC32 Memory Error Controller (MEC) support.
+ *
+ * Put this variable in a separate file so it is only linked in when needed.
+ */
+
+/*
  *  COPYRIGHT (c) 1989-2002.
  *  On-Line Applications Research Corporation (OAR).
  *