libdebugger: Fixes to debugging, ARM support, locking, and gcc-7.1 warnings.

- Add `printk` support to aid multi-core debugging.
- Add lock trace to aid lock debugging.
- Fixes to gcc-7.1 warnings.
- Fixes from ticket #2879.
- Add verbose command controls.
- Change using the RTEMS sys/lock.h API to manage exception threads.
- ARM hardware breakpoint fixes. Support for SMP stepping
  is not implemented, this requires use of the context id
  register.

Closes #2879.

cpukit/libdebugger/rtems-debugger-cmd.c

@@ -1,5 +1,6 @@
 /*
- * Copyright (c) 2016 Chris Johns <chrisj@rtems.org>.  All rights reserved.
+ * Copyright (c) 2016 Chris Johns <chrisj@rtems.org>.
+ * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -180,11 +181,29 @@ static int rtems_shell_main_debugger(int argc, char *argv[])
       return 1;
     }
   }
+  else if (strcasecmp(argv[1], "verbose") == 0) {
+    if (!rtems_debugger_running()) {
+      printf("error: debugger not running.\n");
+      return 1;
+    }
+
+    if (argc == 3 && strcasecmp(argv[2], "on") == 0) {
+      rtems_debugger_set_verbose(true);
+    }
+    else if (argc == 3 && strcasecmp(argv[2], "off") == 0) {
+      rtems_debugger_set_verbose(false);
+    }
+    else {
+      printf("debugger verbose: not on or off\n");
+      return 1;
+    }
+  }
   else if (strcasecmp(argv[1], "help") == 0) {
     printf("debugger [start/stop/help] ...\n" \
            "  start -v -R remote -d device -t secs -P priority -l [stdout,stderr,kernel]\n" \
            "  stop\n" \
            "  remote-debug <on/off>\n" \
+           "  verbose <on/off>\n" \
            "  help\n");
   }
   else {