klippy: Introduce load_config_prefix() for modules that take parameters

Use both load_config() and load_config_prefix() functions when
dynamically loading a module from the extras directory - if the config
section name has parameters in it then use load_config_prefix().

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

klippy/extras/ad5206.py

@@ -26,5 +26,5 @@ class ad5206:
                 self.mcu.add_config_cmd(
                     "send_spi_message pin=%s msg=%02x%02x" % (self.pin, i, val))
 
-def load_config(config):
+def load_config_prefix(config):
     return ad5206(config)