replace a set of #define by a C bit array, remove duplicated extern global variable declaration

executables/main_ru.c

@@ -119,7 +119,8 @@ void exit_function(const char *file, const char *function, const int line, const
 static void get_options(configmodule_interface_t *cfg)
 {
   CONFIG_SETRTFLAG(CONFIG_NOEXITONHELP);
-  get_common_options(cfg, SOFTMODEM_ENB_BIT);
+  IS_SOFTMODEM_ENB = true;
+  get_common_options(cfg);
   CONFIG_CLEARRTFLAG(CONFIG_NOEXITONHELP);
 
   // RCConfig();