monitor/hmp-cmds.c: Clean up hmp_dumpdtb printf

In hmp_dumpdtb(), we print a message when the command succeeds.  This
message is missing the trailing \n, so the HMP command prompt is
printed immediately after it.  We also weren't capitalizing 'DTB', or
quoting the filename in the message.  Fix these nits.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20250206151214.2947842-2-peter.maydell@linaro.org

monitor/hmp-cmds.c

@@ -431,6 +431,6 @@ void hmp_dumpdtb(Monitor *mon, const QDict *qdict)
         return;
     }
 
-    monitor_printf(mon, "dtb dumped to %s", filename);
+    monitor_printf(mon, "DTB dumped to '%s'\n", filename);
 }
 #endif