heater: Support generic gcode_id registration for sensors

Support reading a "gcode_id" parameter from heater/sensor config
sections.

Signed-off-by: Douglas Hammond <wizhippo@gmail.com>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/extras/heater_generic.py

@@ -4,13 +4,5 @@
 #
 # This file may be distributed under the terms of the GNU GPLv3 license.
 
-import logging
-
-class PrinterHeaterGeneric:
-    def __init__(self, config):
-        self.printer = config.get_printer()
-        gcode_id = config.get("gcode_id")
-        self.heater = self.printer.lookup_object('heater').setup_heater(config, gcode_id)
-
 def load_config_prefix(config):
-    return PrinterHeaterGeneric(config)
+    return config.get_printer().lookup_object('heater').setup_heater(config)