Use gdb map in mi-cmds.c

This changes mi-cmds.c to use gdb::unordered_map.

Approved-By: Simon Marchi <simon.marchi@efficios.com>

gdb/mi/mi-cmds.c

@@ -21,12 +21,12 @@
 #include "mi-cmds.h"
 #include "mi-main.h"
 #include "mi-parse.h"
-#include <map>
+#include "gdbsupport/unordered_map.h"
 #include <string>
 
 /* MI command table (built at run time). */
 
-static std::map<std::string, mi_command_up> mi_cmd_table;
+static gdb::unordered_map<std::string, mi_command_up> mi_cmd_table;
 
 /* MI command with a pure MI implementation.  */