docs: put RC modules into their own category (#24847)

src/drivers/rc/crsf_rc/CrsfRc.cpp

@@ -526,6 +526,7 @@ This module parses the CRSF RC uplink protocol and generates CRSF downlink telem
 )DESCR_STR");
 
 	PRINT_MODULE_USAGE_NAME("crsf_rc", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("radio_control");
 	PRINT_MODULE_USAGE_COMMAND("start");
 	PRINT_MODULE_USAGE_PARAM_STRING('d', "/dev/ttyS3", "<file:dev>", "RC device", true);
 

src/drivers/rc/dsm_rc/DsmRc.cpp

@@ -399,6 +399,7 @@ This module does Spektrum DSM RC input parsing.
 )DESCR_STR");
 
 	PRINT_MODULE_USAGE_NAME("dsm_rc", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("radio_control");
 	PRINT_MODULE_USAGE_COMMAND("start");
 	PRINT_MODULE_USAGE_PARAM_STRING('d', "/dev/ttyS3", "<file:dev>", "RC device", true);
 

src/drivers/rc/ghst_rc/GhstRc.cpp

@@ -292,6 +292,7 @@ This module does Ghost (GHST) RC input parsing.
 )DESCR_STR");
 
 	PRINT_MODULE_USAGE_NAME("ghst_rc", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("radio_control");
 	PRINT_MODULE_USAGE_COMMAND("start");
 	PRINT_MODULE_USAGE_PARAM_STRING('d', "/dev/ttyS3", "<file:dev>", "RC device", true);
 	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();

src/drivers/rc/sbus_rc/SbusRc.cpp

@@ -302,6 +302,7 @@ This module does SBUS RC input parsing.
 )DESCR_STR");
 
 	PRINT_MODULE_USAGE_NAME("sbus_rc", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("radio_control");
 	PRINT_MODULE_USAGE_COMMAND("start");
 	PRINT_MODULE_USAGE_PARAM_STRING('d', "/dev/ttyS3", "<file:dev>", "RC device", true);
 	PRINT_MODULE_USAGE_DEFAULT_COMMANDS();

src/drivers/rc_input/RCInput.cpp

@@ -1018,6 +1018,7 @@ This module does the RC input parsing and auto-selecting the method. Supported m
 )DESCR_STR");
 
 	PRINT_MODULE_USAGE_NAME("rc_input", "driver");
+	PRINT_MODULE_USAGE_SUBCATEGORY("radio_control");
 	PRINT_MODULE_USAGE_COMMAND("start");
 	PRINT_MODULE_USAGE_PARAM_STRING('d', "/dev/ttyS3", "<file:dev>", "RC device", true);